Engine Mechanical m3 BMW M3 E36

00 00 249 BMW engine oil service (S50)

Change engine oil and oil filter.

Unfasten main flow oil filter cover - engine oil now flows back into oil pan.

Installation

Tightening torque, refer to TIGHTENING SPECIFICATIONS .

Scheme 23

Replace sealing rings.

Scheme 24

Remove oil filter insert.

Scheme 25

After draining oil from oil-filter housing, unscrew oil drain plug or draw out oil with a vacuum unit or draw out oil with a vacuum unit.

Replace sealing ring.

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

Pour in engine oil. Start engine and allow to idle until oil indicator light goes out. Stop engine and check oil level.

Scheme 26

Note. The screw (1) must not be unscrewed; the remaining residual oil quantity is irrelevant for engine oil service.

If the oil pan is then removed

Scheme 27

11 00 039 Checking compression of all cylinders (S50)

1. Read out fault memory of DME control unit
2. Check stored faults
3. Rectify faults
4. Clear fault memory

Disconnect DME relay in under-hood relay compartment on left rear side of engine compartment.

Unscrew and remove all spark plugs

Screw special tool 11 0 235 by hand into spark plug thread.

Connect special tool 11 0 224.

Depress accelerator pedal and actuate starter motor until compression stops rising.

Compression pressure

Scheme 28

Note. Special tool 11 0 227 can no longer be ordered.

Special tool 11 0 235 replaces special tool 11 0 227.

If a special tool 11 0 227 is available, it still can be used.

Scheme 29

Now clear the fault memory.

11 00 050 Removing and installing engine (S50)

Special tools required

1. 11 0 020

Disconnect negative battery lead.

E36

Lift engine hood into assembly position and remove firewall air manifold.

Z3

Move engine hood to assembly position

Note. The following work must be carried out with a second person assisting. Work instruction applies to left and right sides. Hold engine bonnet/hood. Unclip retainer (1).

Unhook damper and suspend in ball head (2).

Scheme 30

All Models

Remove complete manifold.

Drain coolant.

Remove complete radiator with oil cooler.

Remove transmission.

Remove alternator drive belt.

Remove drive belt for air pump and A/C compressor.

Only for air-conditioning systems

Disconnect plug connection from air conditioning compressor.

Remove air-conditioning compressor from engine mount (pipes remain connected!)

Scheme 31

Only for air-conditioning systems

Completely remove hose clips from air pump.

Remove hoses.

Scheme 32

Only for air-conditioning systems

Disconnect plug connection (1) from air pump.

Unfasten screw connections (2 and 3).

Remove air pump.

Scheme 33

Only for air-conditioning systems

Remove bearing block for air pump (3 screws).

Scheme 34

Only for air-conditioning systems

Completely untighten screw on air conditioning compressor.

Leads remain connected!

Tie air-conditioning compressor to one side, relieving tension on pipes.

Scheme 35

Remove vane pump for hydraulic steering gear from engine bracket and tie back to one side.

Leads remain connected!

Scheme 36

Remove coolant-air guide from alternator.

Scheme 37

Unscrew nut from bottom-right engine mount.

Tightening torque, refer to TIGHTENING SPECIFICATIONS .

Unfasten ground strap on engine support.

Scheme 38

Lower vehicle.

Unscrew nut from bottom-left engine mount.

Tightening torque, refer to TIGHTENING SPECIFICATIONS .

Scheme 39

Remove hydraulic container from engine support arm.

Leads remain connected!

Scheme 40

Loosen fuel supply line and return line.

Scheme 41

Remove cover from plug connections at VANOS control unit.

Scheme 42

Remove ground strap (1) and cable tie (2) from VANOS adjustment unit.

Scheme 43

Disconnect plug connections of solenoid valves (1) and (2) of VANOS adjustment unit.

Scheme 44

Disconnect plug-in connections at holder

1. Solenoid valve 2 on VANOS adjustment unit
2. Position sensor of exhaust camshaft
3. TDC sensor of cylinder 1 on intake camshaft
4. TDC sensor of crankshaft at vibration damper

Scheme 45

Disconnect plug-in connections at holder

1. Throttle potentiometer
2. Position sensor of exhaust camshaft

Scheme 46

Remove cable strap.

Scheme 47

Remove connecting strip from injection valves and lay to one side.

Scheme 48

Unfasten screws.

Remove ignition-coil cover.

Scheme 49

Disconnect plug-in connections at ignition coils.

Scheme 50

Unscrew earth connection (1).

Unfasten retainer on ignition cable guide (2).

Scheme 51

Remove ignition coil cable and cable guide from cylinder head cover.

Scheme 52

Remove ground strap behind cylinder head.

Scheme 53

Unclip diagnosis socket and place to one side with complete wiring harness.

Scheme 54

Unfasten connections on starter motor.

Tightening torque, refer to TIGHTENING SPECIFICATIONS .

Scheme 55

Unfasten connections on alternator.

Tightening torque, refer to TIGHTENING SPECIFICATIONS .

Scheme 56

Unfasten plug connection

1. Coolant temperature sensor for control unit
2. Coolant-temperature sensor for remote-therm sensor

Scheme 57

Unfasten plug connection.

1. Sensor for engine-oil pressure
2. Engine-oil-temperature sensor

Scheme 58

Disconnect plug-in connection at solenoid for vacuum control of non-return valve of air pump.

Scheme 59

Unfasten plug connection

1. Knock sensor for cylinders 1 and 2
2. Knock sensor for cylinders 3 and 4
3. Knock sensor for cylinders 5 and 6

Scheme 60

Disconnect plug-in connection from idle speed control valve.

Scheme 61

Unfasten hose clip (1) and screw (2).

Remove oil separator from cylinder head.

Scheme 62

Retaining rail for engine wiring harness

Unscrew screw.

Removing wiring harness.

Scheme 63

Unscrew screw.

Scheme 64

Unscrew coolant hoses on left-hand side of engine block.

Scheme 65

Unscrew coolant hoses on left-hand side of engine block.

Scheme 66

Unscrew coolant hose from expansion tank.

Scheme 67

Remove hose for tank ventilation from rear of cylinder head.

Remove lower section of steering spindle completely.

Scheme 68

Fit engine to special tool 11 0 020.

Scheme 69

Layout of front engine mount.

Scheme 70

Layout of rear engine mount.

Scheme 71

Unfasten engine support arm from engine block.

Carefully lift out engine.

First screw down right engine mount at bottom, then lower engine from above onto mount.

Scheme 72

Engine identification

Drive in engine numbers at marked surface with impact tool.

Scheme 73

Scheme 74

Scheme 75

Scheme 76

Scheme 77

Scheme 78

Scheme 79

Scheme 80

Scheme 81

Scheme 82

Scheme 83

Scheme 84

Scheme 85

Scheme 86

Scheme 87

11 12 Removing/installing/sealing 000 cylinder-head cover (S50)

Unscrew bolts.

Remove ignition-coil cover.

Scheme 88

Disconnect connector from ignition coils

Scheme 89

Unscrew earth connection (1). Unscrew securing screws at cable guide (2) and put cable guide to one side.

Scheme 90

Remove grommet from cable leading to ignition coils and remove cylinder-head cover.

Scheme 91

Unscrew nuts.

Remove ignition coils.

Scheme 92

Unfasten screws from cylinder-head cover (20 screws on top, in centre and on underside).

Remove cylinder-head cover.

Take off seals.

Scheme 93

Note. Cylinder-head cover is separated from cylinder head by rubber mounts and seals to insulate it from vibration.

Carefully note arrangement of cover retaining fixture.

Scheme 94

1. Cover nut
2. Washer
3. Rubber seal

Installation note

Check cover seal and replace if necessary.

Pre-install inner and outer-cover seals at cylinder head.

Scheme 95

When fitting cylinder-head cover, ensure seal is correctly seated on rear side of cylinder head.

Scheme 96

Install cover retaining fixture and align cover.

Fit cover bolts without initial stress.

Tighten cover bolts crosswise, moving

outwards from centre.

For tightening torque, refer to TIGHTENING SPECIFICATIONS .

11 12 080 Removing and installing or replacing timing case (upper section of cylinder head) (S50)

Remove cylinder head cover

Remove spark plugs

Remove sensor for intake camshaft.

Scheme 97

Remove sensor for exhaust camshaft.

Scheme 98

Remove and install all camshafts

refer to 11 31 019

Extract bucket tappets with Special Tool 11 3 250.

Coat operating faces of bucket tappets with oil and install in correct sequence, each allocated to correct cylinder.

Note. Used bucket tappets must always be re-installed in same tappet bore from which they were removed.

Scheme 99

Place bucket tappets, arranged according to cylinder and in correct sequence, on Special Tool 11 3 030.

Scheme 100

Unfasten connection for engine ventilation.

Extract ventilation pipe by pulling downwards.

Scheme 101

Check O-ring at engine ventilation and replace if necessary.

Scheme 102

Unfasten screws on front timing case.

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

Scheme 103

Remove all screws from timing case.

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

Scheme 104

Remove timing case.

Scheme 105

Clean sealing faces at cylinder head and degrease.

Check O-rings and replace if necessary.

Scheme 106

Clean sealing face at timing case and degrease.

Apply light, even coating of 3 Bond 1209 sealing compound.

Scheme 107

11 12 100 Removing and installing cylinder head (S50)

Removing intake air manifold

refer to 11 61 050

Removing timing case

refer to 11 12 080

Scheme 108

Remove exhaust system

Removing both exhaust manifolds

refer to 11 62 140

Removing coolant thermostat

refer to 11 53 000

Remove hose on idle speed actuator (1).

Remove hose on engine breather (2).

Scheme 109

Unfasten hose clip (1) and screw (2).

Remove oil separator from cylinder head.

Scheme 110

Unscrew holder for fuel feed and return lines.

Scheme 111

Unscrew pipe for fuel-pressure regulator between idle-speed control valve and activated-carbon filter with holder.

Scheme 112

Unscrew activated-carbon filter pipe.

Unscrew coolant connecting pipe at cylinder head.

Note. Check earth strap.

Scheme 113

Loosen hose clamp at check valve and pull off hose.

Unscrew holder for air-injection pipe at engine block.

Scheme 114

Unfasten fuel delivery line (1) and fuel return line (2) and vacuum hose from injection pipe.

Scheme 115

Disconnect vacuum hose.

Scheme 116

Disconnect water hose between cylinder head and water valve.

Scheme 117

Unscrew screws at front of cylinder head.

Remove holder for plug-in connections.

Tighten screws only after tightening cylinder-head bolts.

Scheme 118

Unscrew cylinder-head bolts (moving inwards) in sequence 14 ... 1.

1. Remove cylinder head.
2. Remove cylinder-head seal.

Scheme 119

Clean sealing face of cylinder head and crankcase; if necessary, use hardwood scraper to remove sealant compound. Make sure that no sealant compound falls into the oil and coolant channels.

Coat projection between crankcase and timing-case cover with 3 Bond 1209 sealing compound.

Scheme 120

Check that dowel sleeves are undamaged and correctly located.

Fit new cylinder-head seal.

Scheme 121

No oil is permitted in the threaded bores in the crankcase. (Risk of cracks, incorrect tightening values).

Scheme 122

Fit cylinder head and tighten new screws (lightly oiled) in sequence 1 ... 14.

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

Scheme 123

Note. For torsion angle adjustment, use special tool 00 9 120 or special tool 11 2 110.

Scheme 124

11 12 101 Replacing cylinder head gasket (S50 S54)

Operation is identical to Removing and installing cylinder head.

11 12 500 Removing and installing cylinder head - engine removed (S50)

Remove the timing-gear case, refer to 11 12 508

Rest of procedure is described in section on removing cylinder head

refer to 11 12 100

11 12 501 Replacing cylinder head - engine removed (S50)

Same scope of work as for removing and installing cylinder head

refer to 11 12 500

11 12 503 Dismantling and reinstalling cylinder head - cylinder head removed (S50)

Special tools required

1. 00 1 490
2. 11 0 192
3. 11 0 194
4. 11 0 342
5. 11 0 343
6. 11 1 045
7. 11 1 065
8. 11 1 067
9. 11 1 071
10. 11 3 411
11. 11 3 412

Remove air guide from cylinder head.

Remove stud bolts from air guide on cylinder head.

Scheme 125

Installation

Insert stud bolts with screw retaining compound.

Replace seal.

Scheme 126

Unfasten screw on axle pin for guide wheel.

Scheme 127

Remove axle pin with standard extractor tool over M10 thread.

Remove guide wheel.

Scheme 128

Installation

Install guide wheel in correct direction.

Align opening (1) (positioning of axle pin) towards top.

Replace sealing ring (2).

Scheme 129

Remove sliding rail

Remove retaining ring on axle pin for sliding rail.

Scheme 130

Remove axle pin with standard extractor tool over M8 thread.

Remove sliding rail.

Scheme 131

Installation

Replace sealing ring.

Scheme 132

Open screw plug on control valve.

Installation

Replace seal.

Scheme 133

Insert M8x50 screw (1) with continuous thread, nut (2) and strong washer (3) with larger outside diameter (e.g. washer of cylinder head bolt) in control valve (4).

Remove control valve (4) by turning nut (2).

Scheme 134

Installation

Screw bolt (1) with nut (2) and shim (3) into control valve (4).

Adjust distance between washer (3) and control valve (4) to X = 20 + 1 mm.

Scheme 135

Installation

Move control valve into installing position by tapping gently on head of screw.

Scheme 136

Provide special tools for removing valve springs.

Secure special tool 11 1 065 to special tool 00 1 490.

Scheme 137

1. Special tool 11 1 071
2. Special tool 11 1 067
3. Special tool 11 0 192
4. Special tool 11 1 045
5. Special tool 11 0 194
6. Special tool 11 0 342
7. Special tool 11 0 343
8. Special tool 11 3 411

Secure special tool 11 3 411 with special tool 11 1 045 in special tool 11 1 065 .

Assemble special tools.

Scheme 138

Secure cylinder head to special tool 11 1 065 .

Note. Secure cylinder head from below, through locating board, with special tool 11 3 412 in spark plug threads.

Scheme 139

If necessary, remove throttle assembly completely.

Scheme 140

Remove coolant pipe and lift off cover.

Installation

Replace sealing rings (1).

Clean and degrease sealing face.

Replace seal between cover and cylinder head.

Scheme 141

Remove all valve springs.

Replace all stem seals.

Remove all valves.

11 12 508 Removing and installing or replacing timing case (upper section of cylinder head) (S50)

(engine removed)

Unfasten heat-protection plate on manifold (6 screws).

Scheme 142

Remove exhaust manifold.

Coat thread with copper paste.

Replace nuts.

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

Scheme 143

Replace seals.

Smooth face of seals points towards cylinder head.

Scheme 144

Remove engine carrier.

Scheme 145

Secure engine with retaining plate - special

tool 11 8 040 - to assembly frame - special tool 00 1 490.

Note. Special tool 11 3 350 can be reused after rework.

Check access to engine block.

Scheme 146

Removing and installing or replacing timing case

refer to 11 12 080

11 12 527 Remachining a valve seat - cylinder head disassembled (S50 / S54)

Machine valve seat surface with special tool 00 3 520 or with 00 3 580 in accordance with tool manufacturer's instructions.

Scheme 147

Note. After machining valve-seat surface: Remachine outside and inside diameters with correction milling tool to the specified diameters until you obtain valve seat width (5).

Scheme 148

1. Valve-seat angle
2. Correction angle, outside
3. Correction angle, inside
4. Outside diameter of seat face
5. Valve-seat width

Items (1) to (5).

11 12 595 Checking a valve guide for wear - valve removed (S50 / S54)

Measure tilt clearance.

For measurement, install a new valve in such a way that the end of the valve shaft seals the valve guide.

Mount dial gauge and measure tilt clearance.

Scheme 149

In event of excessive tilt clearance: replace cylinder head.

11 12 729 Checking that cylinder head is watertight - cylinder head dismantled (S50)

Close coolant apertures with special tool 11 1 421/422/401/402/437 or /403.

Note. Special tool 11 1 437 for S50 B30 Special tool 11 1 403 for S50 B32

Scheme 150

Immerse cylinder head in a water bath.

Test pressure 4.5 bar

Check cylinder head for escaping air (cracks).

Note. If necessary, add cleaning agent to water bath.

Scheme 151

11 13 000 Removing and installing, sealing or replacing oil pan (S50)

Note. For removal of oil pan, front axle support must be lowered.

There is no need to perform a front axle alignment check.

Remove windshield wash pump (1) from water container on windshield washing unit, disconnect electrical connections (2) and unfasten screw (3).

Remove water container from windshield washing unit.

Scheme 152

Removing intake filter housing

Remove air intake duct from air accumulator.

Scheme 153

Remove guide pipe for dipstick.

Check O-ring, replacing if necessary.

Scheme 154

Unfasten fluid tank on vane pump for power steering from engine support arm and pull forwards.

Scheme 155

Prepare special tool 00 0 200 with special tool 00 0 201/202/204/206.

Scheme 156

If necessary, unfasten electrical connections from air conditioning compressor and place to one side.

Fit special tool 00 0 206 to engine mounting.

Scheme 157

Carefully lift engine approx. 5 mm.

Scheme 158

Unfasten main flow filter cover enabling engine oil to drain back into oil pan.

Replace sealing rings.

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

Scheme 159

Drain engine oil.

Note. On version with two oil drain plugs, unfasten both drain plugs.

Replace sealing ring.

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

Scheme 160

Remove underbody protection from front of assembly

Removing alternator drive belt

refer to 11 28 010

Unscrew air pipe from suction-filter housing on air pump.

Scheme 161

Unfasten complete air pipe from oil pan.

Scheme 162

Unscrew vane pump for power steering and fasten to one side.

Note. Lines remain connected.

Scheme 163

Disconnect oil strainer hose from oil pan.

Scheme 164

On version with oil level sensor

Disconnect plug connector on oil level sensor.

Unscrew engine mountings on bottom left and right.

Replace nuts.

Unfastening steering spindle from steering gear

Scheme 165

Unfasten cross pipe.

Scheme 166

On S50 B32 (with two oil drain plugs in oil pan)

Unfasten plunger rod (pendulum support) on stabilizer and pull stabilizer forwards to remove.

Comply with installation instructions and specified tightening torques

refer to TIGHTENING SPECIFICATIONS .

Scheme 167

On S50 B32 (with two oil drain plugs in the oil pan)

Unfasten cover.

Replace sealing ring.

Scheme 168

Support front axle carrier.

Unfasten left and right transverse links from engine carrier. Unfasten screw connection on front axle carrier and lower the front axle carrier.

Note. The steering gear must not be disconnected from the front axle carrier.

Unscrew oil pan screw connection on transmission end.

Scheme 169

Unfasten oil pan screws connecting it to end cover.

Scheme 170

Unscrew oil pan screw connection on engine end.

Scheme 171

Move oil pan backwards.

Scheme 172

Sealing faces clean and free of seal debris.

Coat impact edges of separating face with 3 Bond 1209.

Check seal, replacing if necessary.

Scheme 173

Insert all screws on transmission end, without preload at this stage. Tighten down screws on engine end.

Tighten screws on transmission end.

Scheme 174

11 13 500 Removing and installing, sealing or replacing oil pan (S50)

Engine removed.

Open oil drain plug or drain off oil.

Replace sealing ring.

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

Scheme 175

Unscrew heat-protection plate from top of exhaust manifold (6 screws).

Scheme 176

Remove exhaust manifold.

Coat thread with copper paste

Replace nuts.

For tightening torque

refer to TIGHTENING SPECIFICATIONS .

Scheme 177

Replace seals.

Smooth face of seals points towards cylinder head.

Scheme 178

Remove engine carrier.

Scheme 179

Secure engine to assembly frame, special tool 00 1 490 with special tool 11 8 040.

Note. Special tool 11 3 350 can be reused after rework. Check access to engine block.

Scheme 180

Remove air hose between air pump and non-return valve.

Dismantle guide pipe for dipstick and remove.

Scheme 181

Check/replace sealing ring.

Scheme 182

Unfasten all screws and remove oil pan.

Scheme 183

Sealing faces clean and free of seal debris.

Coat contact edges of separating face with 3 Bond 1209.

Check seal, replacing if necessary.

Scheme 184

To prevent torsion stress in subsequent transmission assembly operations, align transmission end on engine block.

Scheme 185

11 14 110 Removing and installing, sealing or replacing timing case cover (S50 / S54)

Special tools required

1. 00 0 200

Unscrew oil sump.

Note. After removing oil sump, reinstall front axle support provisionally and remove special tool 00 0 200.

Remove cylinder head .

Remove vibration damper .

Remove radial seal .

Note. Install new radial seal only after

installing timing case cover.

If necessary, remove pulse generator from timing case cover.

Scheme 186

Remove vane pump from timing case cover (lines remain connected).

Unfasten screws and remove timing case cover.

Scheme 187

Note. Dowel pins for location purposes are pressed into the timing case cover.

Keep sealing faces clean and free of oil. Check dowel pins for damage and correct installation position.

Replace seals.

Apply a thin coat of Drei Bond 1209 sealing compound to ends of seals at front and rear.

Position seals on dowel pins in timing case cover.

Fit timing case cover with seals, insert all screws and pretighten to approx.

5 Nm.

Fully tighten all screws in alternate sequence.

Tightening torque, 11 14 1AZ. TIGHTENING SPECIFICATIONS .

Scheme 188

Replace radial sealing ring.

Assemble engine.

11 14 141 Replacing radial seal in lower timing case cover (S50 / S54)

Special tools required

1. 11 1 220
2. 11 2 380
3. 11 2 384
4. 11 5 090
5. 11 7 240

Remove vibration damper.

Note. Illustrations show the S54.

The special tools and the actual procedure are identical for the S50.

Removal

Fit special tool 11 2 384 on crankshaft.

Scheme 189

Screw in special tool 11 2 380 until it is firmly connected to the radial seal.

Remove radial seal by tightening in the screw.

Scheme 190

Scheme 191

Fit special tool 11 7 240 on sprocket wheel.

Oil sealing lips of new radial seal (1).

Push radial seal (1) over special tool 11 7 240 until it rests against timing case cover.

Remove special tool 11 7 240 .

Install special tool 11 5 090 and tighten down.

Scheme 192

Draw in new radial seal with special tool 11 1 220 until it is flush with timing case cover.

Scheme 193

11 14 151 Replacing crankshaft radial seal (transmission side)

Note. This repair instruction is valid for the following engines

1. M40 / M42 / M43 / M43TU / M44
2. M50 / M52 / M52TU / M54 / M56
3. S52 / S54

Necessary preliminary tasks

1. Remove gearbox
2. Drain off engine oil
3. Remove flywheel

Unfasten oil sump screws on transmission end.

Loosen oil pan.

Scheme 194

Release screws in end cover at rear.

Carefully detach oil sump gasket from end cover, remove end cover.

Note. After removing end cover: check oil sump gasket for damage.

If necessary, remove oil sump and replace oil sump gasket.

Scheme 195

Note. As from 4/98, a new type of radial seal is used in the Series and as a replacement. This radial seal may only be supported with a "support bushing".

If the radial seal is supported without the support bushing (1) for more than six months, operational reliability will no longer be assured and the radial seal must not be used any further.

Scheme 196

Distinguishing feature

1. (1) New version "without hose spring"
2. (2) Old version "with hose spring"

Scheme 197

Note. The end cover is offered in the kit with a radial seal.

If necessary, lift out the radial sealing ring and drive in new sealing ring using special tool 11 1 260 in conjunction with special

tool 00 5 500.

Scheme 198

Check dowel sleeves (1) for damage and correct installation position.

Replace seal (2).

Apply thin, uniform coat of Drei Bond 1209 sealing compound to edges of joint on oil pan.

Scheme 199

Scheme 200

Note. When fitting the end cover with radial seal on the crankshaft, it is only permitted to use the "support bushing (1)" as an installation tool.

Lubricate contact face of crankshaft.

Scheme 201

Note. Screw threads (1) are coated with sealing compound.

Replace screws (1).

Insert all screws and tighten down end cover.

Scheme 202

Note. Keep the support bushing (1) of the new radial seal version as a "special tool", then render the special tool 11 2 213 unusable and dispose of it.

The old and new radial seal versions can be installed with the support bushing (1).

Scheme 203

11 21 500 Replacing crankshaft (S50)

(engine removed)

Fitting timing case cover to underside

refer to 11 14 110

Removing end cover from back: this operation is described in section on replacing radial seal in crankshaft

refer to 11 14 151

Removing all pistons

refer to 11 25 530

If the permitted end float is exceeded, check crankshaft, pilot bearing shells and engine block and replace where necessary.

Replacing main bearing shells on crankshaft

refer to 11 21 531

Scheme 204

Unfasten screw, remove sprocket wheel.

Scheme 205

Remember to fit hollow sleeve in sprocket wheel.

Scheme 206

Unfasten screw connection on main bearing.

Remove main bearing caps 1 ... 7.

Lever out crankshaft.

Replacing main crankshaft bearing shells

refer to 11 21 531

Scheme 207

Note. Bearing covers 1 ... 5 are marked on the outlet (exhaust) side. Bearing covers 6 and 7 are not marked. Bearing cover 6 is the guide bearing.

Scheme 208

Coat bearing shells with oil.

Install crankshaft.

Fit bearing covers (1 ... 7) (bearing 1 on camshaft input side) in such a way that the grooves in the bearing shell

guide are arranged down one side.

Align bearing cover precisely.

Scheme 209

Note. Remember to fit suction pipe support to main bearing 5.

Scheme 210

Note. Always replace main bearing screws with new ones. No oil is permitted in the blind bores (danger of cracking) Screws washed and oiled.

Tightening specifications for main bearing

1. Tighten all screws on main bearing cover with torque.
2. Unfasten screws on main bearing cover 6.
3. Strike back and front of crankshaft with plastic centre thrust bearing (do not damage crankshaft.
4. Tighten screws of main bearing cover.
5. Tighten all screws of main bearing cover with special tool 11 2 110 or special tool 00 9 120

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

Replacing conrod bearing shells

refer to 11 24 571

Replacing grooved ball bearing in crankshaft

refer to 11 21 571

Scheme 211

11 21 531 Replacing all crankshaft main bearing shells (S50)

(engine dismantled)

Note. For piston cooling, spray nozzles are installed on underside of cylinder between the bearing seats.

Scheme 212

Scheme 213

When replacing the bearing shells (including on replacement crankshaft), classification for bearing shell arrangement in engine block is waived.

Only install yellow bearing shells in engine block.

Scheme 214

Note. Install bearing shells with continuous lubricant one retaining lug in engine block. Fit bearing shells without continuous lubricant side two retaining lugs in bearing cover.

Scheme 215

Note. The axial guide on the crankshaft is fitted to bearing point 6.

Insert pilot bearing shell in the engine block.

Scheme 216

The crankshaft is marked with yellow, green or white paint, depending on the tolerance of the main bearing spigot.

Scheme 217

The bearing shell classification for the bearing cover is marked on the crankshaft in yellow, green or white paint.

Scheme 218

The bearing shells are marked with yellow, green or white paint.

1. Bearing shell
2. Guide bearing

Note grinding stage of main bearing spigot.

Scheme 219

Note. The bearing covers 1 ... 5 are designated on the exhaust end. Bearing covers 6 and 7 are not designated. Bearing cover 6 is a thrust bearing.

Scheme 220

Check clearance on main crankshaft bearing.

Install crankshaft and place special tool 00 2 590 (Plastigage Type PG1) on the oil-free crankshaft.

Do not twist crankshaft.

Scheme 221

Install main bearing cover with grooves in main bearing shell mount on one side.

Align main bearing cap flush with side of bearing seat.

Scheme 222

Note. To check main bearing clearance, use old main bearing screws. No oil is permitted in the blind bores (danger of cracking). Wash and oil main bearing screws.

Tightening specifications for main bearing

1. Tighten screws to torque.
2. Tighten down screws with special tool 00 9 120 torsion angle.

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

Scheme 223

Remove main bearing cover and read off bearing clearance on width of squashed plastic thread using the measuring scale.

If necessary, fit new bearing shells with a different color code to correct bearing clearance.

Face runout on crankshaft bearing

Scheme 224

Color code for shaft diameter / bearing size

1. crankshaft Ge = yellow Gn = green Ws = white
2. bearing clearance
3. bearing shells: Yellow Green
4. bearing cover

Scheme 225

Note. Remove plastic thread. Coat main bearing shells and crankshaft with engine oil.

Install main bearing cover with grooves in

main bearing shell mount on one side.

Align main bearing cap flush with side of bearing seat.

Scheme 226

Note. Always replace the main bearing screws with new ones. No oil is permitted in the blind bores (danger of cracking). Wash and oil main bearing screws.

Tightening specifications for main bearing

1. Tighten all screws on main bearing cover with torque.
2. Unfasten screws on main bearing cover.
3. Strike front and back of crankshaft with plastic centre the thrust bearing.
4. Tighten down screws of main bearing cover.
5. Tighten all screws in main bearing cover with tool 11 2 110 or tool 00 9 120 with torsion angle.

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

If the permitted end float is exceeded, check crankshaft, pilot bearing shells and engine block and replace where necessary

Scheme 227

Scheme 228

11 21 571 Replacing grooved ball bearing in crankshaft (M52 / S52 / M52TU / M54 / S50 / S54)

Special tools required

1. 00 5 500
2. 11 2 340
3. 11 2 350

(clutch removed)

Scheme 229

Version with grooved ball bearing

Remove guide bearing with special tool 11 2 340.

Scheme 230

Install new thrust bearing and drive firmly

home with special tool 11 2 350 in

conjunction with special tool 00 5 500.

Scheme 231

11 22 500 Removing and installing or replacing flywheel (S50) (clutch removed)

Block the flywheel using Special Tool 11 2 170.

Scheme 232

Unfasten screws and remove flywheel.

Clean thread and install new micro encapsulated screws.

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

Scheme 233

Remember to fit hollow bush.

Scheme 234

11 23 010 Removing and installing or replacing vibration damper (S50)

Removing fan coupling with fan shroud

refer to 11 52 020

Remove front underbody protection.

Remove drive belt for alternator

refer to 11 28 010

S50 B32

Unfasten plate for TDC check.

Check dowel sleeves for signs of damage and correct installation. Note direction of installation for plate used for establishing TDC position.

Scheme 235

Unfasten screws and remove belt pulley.

Scheme 236

Arrest vibration damper with Special Tool 11 2 490.

Release screws and remove vibration damper.

Scheme 237

Installation location of vibration damper is secured by a dowel pin.

Scheme 238

Remember to fit washer under screws.

Replace screws.

For tightening torque

refer to TIGHTENING SPECIFICATIONS .

Scheme 239

11 24 571 Replacing all conrod bearings (S50) (pistons removed)

Special tools required

1. 00 2 590
2. 00 9 120
3. 11 2 110

Install new bearing shells.

Insert one red and one blue bearing shell for each conrod.

Scheme 240

Install piston.

Check conrod bearing clearance.

Piston in BDC position.

Fit special tool 00 2 590 (Plastigage Type PG 1) to the oil-free crankshaft.

Fit bearing caps so that pair numbers match up.

Scheme 241

Use the old conrod bolts to check conrod clearance.

Tighten down conrod bolts with special tool 00 9 120 or with special tool 11 2 110.

see TIGHTENING SPECIFICATIONS

Scheme 242

Remove bearing cap and read off bearing play at width of flattened plastic thread with assistance of measurement scale.

Scheme 243

Removal

Removal of pistons is described separately from installation.

Assembly sequence for removal and installation is different.

Remove cylinder head

refer to 11 12 500 .

Remove oil sump

refer to 11 13 500 .

Remove oil pump

refer to 11 41 000 .

Remove oil lever.

Scheme 244

Unscrew conrod bearing cover.

Remove conrod with piston from cylinder head side.

Scheme 245

Lift out retaining ring and press out piston pin.

Scheme 246

Installation of pistons is described separately from removal. Assembly sequence for removal and installation is different.

Before installation, measure piston installation clearance. Measure piston diameter with micrometer at measuring point A from bottom edge of piston and offset at 90° to the axis of the piston pin.

Scheme 247

Adjust micrometer on cylinder bore of engine block and set plug gauge on micrometer to zero. Measure bottom, center and top of cylinder bore in direction of travel and direction of engine rotation.

Scheme 248

It should be possible to press piston pin into bush by hand using only slight pressure. Clearance should then be minimal.

Scheme 249

If necessary, replace connecting rods.

Note. Inside any one engine, all connecting rods must share the same weight class.

Spare connecting rods can only be obtained in complete sets.

Replace conrod bearing

refer to 11 24 571 .

Scheme 250

Fit connecting rod with piston pin to piston in such a way that both of the visible pair numbers on the installation direction arrow on the piston point to the right.

Scheme 251

Install retaining ring.

Scheme 252

Insert special tool 11 3 480 in connecting rod.

Scheme 253

Lightly coat pistons and piston rings with oil.

Align contact points of piston rings (offset at approx. 120°, but not over piston pin lug).

Press together piston rings using special tool 11 2 260.

Scheme 254

Install pistons with arrows pointing towards camshaft drive.

The entire circumference of the tightening strap must be flush with the crankcase.

Scheme 255

Attach crankpin to connecting rod.

Scheme 256

Apply light coat of oil to connecting-rod bearing shells.

Place bearing caps in position, making sure that matching numbers are paired.

Install new conrod bolts.

Scheme 257

Tighten down conrod bearing with special tool 00 9 120 or with special tool 11 2 110.

Tightening specification, see TIGHTENING SPECIFICATIONS .

Scheme 258

Install oil lever.

Install oil pump

refer to 11 41 000 .

Install oil sump

refer to 11 13 500 .

Install cylinder head

refer to 11 12 500 .

Scheme 259

11 25 671 Replacing piston rings for all pistons (S50) (pistons removed)

Remove piston rings with piston ring compressing pliers.

Note. It might not be possible to find the identification mark on used piston rings.

Lay piston rings aside in correct sequence and installed position.

Always fit new pistons in conjunction with new piston rings.

Scheme 260

Install piston rings with the word "TOP" facing the piston base.

1. Rectangular ring
2. Tips - minute ring "Top" (note installation position)
3. Slotted oil ring with hose spring clip

Scheme 261

Arrange piston ring contact points offset at approx. 120° to one another, but not over the piston pin lug.

Measure axial play.

Scheme 262

Measure end clearance

Scheme 263

11 28 010 Replacing alternator drive belt (S50)

Note. If the drive belt are to be reused, mark the rotation direction and reinstall the drive belt with the same rotation direction.

Removing fan coupling with fan wheel and fan cowl

refer to 11 52 020

Remove air-pump drive belt

refer to 11 72 041

Lift protective cover off tensioning wheel.

Scheme 264

Insert a hexagon key in the tensioner bolt. Slowly rotate clockwise to compress the tensioning element (1) and to relieve tension on the drive belt.

Remove drive belt.

Scheme 265

Check drive belt for coolant and oil residue and replace if necessary.

Scheme 266

Layout of drive belt.

When fitting drive belt, ensure it is correctly located on the pulleys.

Scheme 267

11 28 020 Replacing tensioner for alternator drive belt (S50)

Remove drive belt for alternator

refer to 11 28 010

Lift off protective cover.

Scheme 268

Remove tension roller.

Scheme 269

Remove bearing block.

Scheme 270

Unscrew screw.

Remove and replace belt tensioner.

Scheme 271

Note. The hydraulic belt tensioner is filled with oil. Always store removed elements upright. Incorrectly stored elements can usually be vented by pressing into installed position several times.

Scheme 272

11 31 005 Checking timing of camshafts (S50 B32)

Remove fan coupling with fan shroud.

Remove connector strip for fuel injection valves (1), lift over fuel injection pipe and air lead and place to one side (2).

Scheme 273

Remove cylinder head cover.

Remove spark plugs.

Fit special tool 11 5 100 to four screws on crankshaft hub.

Scheme 274

Bar engine in direction of rotation as far as TDC firing position of first cylinder.

Secure vibration damper with special tool 11 2 300.

Scheme 275

When the engine is switched off, VANOS moves the camshafts to a position which is advantageous to engine starting.

Remove cover from plug connectors.

Scheme 276

Unscrew oil pipe at VANOS control unit.

Scheme 277

Fit special tool 11 7 350 to VANOS adjustment unit.

Connect up compressed air (2 ... 8 bar).

Scheme 278

Disconnect plug connection on solenoid valves on exhaust side.

Connect special tool 12 6 412 and special tool 12 6 410 to the solenoid valves on the exhaust end.

Connect special tool 12 6 410 to correct terminals on vehicle battery.

Depress toggle switch on special tool 12 6 412 in direction of VANOS splined shaft and hold down.

Scheme 279

At the same time, rotate exhaust camshaft at hex head against direction of rotation until the camshaft noticeably reaches the stop.

Note. If necessary, press toggle switches on special tool 12 6 412 several times in both directions until camshaft starts to move.

Scheme 280

Disconnect plug connection of solenoid valves on intake end.

Connect special tool 12 6 412 to the solenoid valves on the intake end.

Depress toggle switch on special tool 12 6 412 in direction of VANOS splined shaft and hold down.

Scheme 281

At the same time, rotate intake camshaft at hex head against direction of rotation until the camshaft noticeably reaches the stop.

Note. If necessary, press toggle switches on special tool 12 6 412 several times in

both directions until camshaft starts to move.

Scheme 282

Note. The engine is at the TDC firing position of the first cylinder. The cam tips of the exhaust and intake camshafts point to each other. The grooves in the exhaust and intake camshafts point to the grooves in the first bearing cover.

Scheme 283

Disconnect special tool 12 6 412 from the solenoid valves.

Disconnect compressed air.

Remove special tool 11 7 350.

Scheme 284

Remove special tool 11 2 300.

Scheme 285

Fit special tool 11 5 100 to four screws on crankshaft hub.

Scheme 286

Scheme 287

Continue to bar engine in direction of rotation through two complete revolutions until the first cylinder is at TDC firing position. Secure vibration damper with special tool 11 2 300.

Note. The grooves in the exhaust and intake camshafts are aligned with the grooves in the first bearing covers.

Scheme 288

Insert special tool 11 5 080 into intake camshaft.

Note. Special tool 11 5 080 must rest on the timing case without a gap.

Scheme 289

Insert special tool 11 5 080 into exhaust camshaft.

Note. Special tool 11 5 080 must rest on the timing case without a gap.

Scheme 290

If necessary, adjust timing of camshaft, refer to 11 31 505

Remove special tool 11 5 080.

Remove special tool 11 2 300.

Scheme 291

Insert screw connections in solenoid valves.

Fit cover to plug connections.

Scheme 292

Fit oil pipe to VANOS adjusting unit.

Tightening Torque, refer to TIGHTENING SPECIFICATIONS .

Assemble engine.

Scheme 293

11 31 019 Replacing all camshafts (S50 B30)

Remove bulkhead heater (air collector).

Remove fan clutch with fan cowl, refer to 11 52 020 .

Unfasten screw connection on cover cap.

Scheme 294

Disconnect air-pump plug-in connection (1).

Scheme 295

Unscrew earth connection (1).

Scheme 296

Disconnect connectors of solenoid valves (1) and (2).

Note. Wires are marked.

Scheme 297

Mark and disconnect plug-in connections at front.

Sensor for exhaust camshaft (2)

Pulse sensor on vibration damper (4)

Scheme 298

Mark and disconnect plug-in connections at top.

Throttle potentiometer (1)

Sensor for intake camshaft (2)

Scheme 299

Pull plug strip off fuel injectors. Lift (1) over injection pipe and air hose, and lay to one side (2).

Scheme 300

Remove cylinder head cover

Remove spark plugs.

Removal and installation of VANOS control unit and camshafts are described separately. Assembly sequence for removal and installation is different.

Unscrew oil pipe at VANOS control unit.

Scheme 301

Remove TDC sensor for cylinder identification.

Scheme 302

Unfasten upper screws 1 and 5 from VANOS adjustment unit.

Scheme 303

Unscrew end cover (VANOS bridge) on timing case.

Scheme 304

Fit special tool 11 5 100 to four screws on crankshaft hub.

Scheme 305

Rotate engine engine-wise until groove on pilot bearing in intake camshaft is aligned with groove in 1st bearing cover.

Scheme 306

Turn crankshaft further in engine direction of rotation until next two bolts of sprocket on VANOS gearbox are accessible.

Slacken these two bolts approx. 2 turns, but do not remove.

Repeat procedure, slacken further 2 bolts approx. 2 turns, but do not remove.

Scheme 307

Rotate engine engine-wise until groove on pilot bearing in intake camshaft is aligned with groove in 1st bearing cover.

Scheme 308

Note. Due to technical revision, the dowel bore in the flywheel is discontinued from 9/93. The Parts Service will now only supply flywheels without dowel bores.

Check firing TDC position of cylinder 1 on mark between vibration damper and underside of timing case cover.

Scheme 309

On flywheels produced before 9/93, secure crankshaft in TDC position with special tool 11 2 300.

Scheme 310

Slacken remaining two bolts on chain wheel on VANOS transmission approx. 2 turns, but do not remove.

Scheme 311

Unscrew bolts 6 to 9 of VANOS control unit.

Scheme 312

Scheme 313

Pull off VANOS control unit together with splined shaft.

Remove drive for VANOS radial piston pump.

Scheme 314

Remove chain tensioning piston with spring, refer to 11 31 090 .

Scheme 315

Remove chain guide from timing chain between intake and exhaust camshafts.

Scheme 316

Detach sprocket and input shaft for VANOS radial piston pump from exhaust camshaft using special tool 11 3 470.

Scheme 317

Remove sprocket wheel and input shaft for VANOS radial piston pump from exhaust camshaft.

Remove chain.

Scheme 318

Fit open-end wrench to hex on intake camshaft.

Scheme 319

Rotate inlet camshaft inwards with opened wrench until cam tips of cylinder 1 are aligned horizontally with camshaft.

Scheme 320

Fit special tool 11 3 400 to depress the inlet camshaft and screw into spark plug threads of cylinders 2 and 5.

Scheme 321

Tightening Torque, refer to TIGHTENING SPECIFICATIONS .

Preload the intake camshaft by rotating the eccentric shaft.

Unscrew all nuts from bearing cover on intake camshaft.

Scheme 322

Relieve tension on special tool 11 3 400 and remove.

Remove bearing cover and lift out intake camshaft together with sprocket wheel.

Note. Use wire to prevent chain from slipping downwards.

Scheme 323

If necessary, replace VANOS transmission, refer to 11 36 520 .

Fit open-end wrench on hex of exhaust camshaft.

Scheme 324

Rotate exhaust camshaft with open-end wrench until cam tips of cylinder 1 are horizontally aligned with camshaft.

Scheme 325

Fit special tool 11 3 400 to press down exhaust camshaft and screw into spark plug threads of cylinders 2 and 5.

Scheme 326

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Preload exhaust camshaft by rotating eccentric shaft.

Unscrew all nuts for bearing cover on exhaust camshaft.

Scheme 327

Relieve tension on special tool 11 3 400 and remove.

Remove bearing cover and lift out exhaust camshaft.

Scheme 328

Installation of VANOS adjusting unit and camshafts is described separately from removal. Assembly sequence differs between removal and installation.

Install exhaust camshaft so that cams of cylinder 1 point horizontally inwards.

Scheme 329

Fit bearing covers.

Scheme 330

Fit special tool 11 3 400 to press down exhaust camshaft and screw into spark plug threads of cylinders 2 and 5.

Scheme 331

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Preload exhaust camshaft by rotating eccentric shaft.

Align bearing cover by hand until bearing cover and timing case are located over hollow dowels.

Fit nuts to bearing cover of exhaust camshaft and tighten down.

Scheme 332

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Untighten and remove special tool.

Install inlet camshaft together with VANOS transmission and position timing chain so that cams of cylinder 1 point horizontally inwards.

Scheme 333

Fit bearing covers.

Scheme 334

Fit special tool 11 3 400 to depress the intake camshaft and screw into spark plug threads of cylinders 2 and 5.

Scheme 335

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Preload the intake camshaft by rotating the eccentric shaft.

Do not tighten bearing-cap bolts at this time.

Scheme 336

Mount end cover (VANOS bridge) on timing case, but do not tighten bolts at this time.

Scheme 337

Tension timing chain between crankshaft and VANOS gearbox sprocket.

Ensure that timing chain between crankshaft and VANOS gearbox sprocket is not loose.

Scheme 338

Check whether sensor pin on chain wheel of VANOS transmission aligns with marking on end cover.

Scheme 339

If applicable, determine amount of deviation.

Loosen chain using special tool 11 3 400 to make corrections.

With chain lifted, turn VANOS gearbox sprocket in opposite direction to deviation.

Apply preload to crankshaft once again by rotating eccentric shaft.

Scheme 340

Check whether sensor pin on chain wheel of VANOS transmission aligns with marking on end cover.

Scheme 341

Note. When checking also ensure that timing chain between crankshaft and sprocket is tensioned.

Scheme 342

Repeat procedure until sensor pin on chain wheel of VANOS transmission aligns with marking on end cover.

Scheme 343

Remove end cover (VANOS bridge) once again.

Scheme 344

Align bearing cover by hand until bearing cover and timing case are located over hollow dowels.

Fit bearing cover nuts on intake camshaft and tighten down.

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Untighten and remove special tool.

Scheme 345

Fit open-end wrench on hex of exhaust camshaft.

Scheme 346

Rotate exhaust camshaft with open-end wrench upwards from horizontal position until groove on camshaft guide bearing aligns with groove on 1st bearing cap.

Scheme 347

Note. Relative positions of sprocket wheel and marker wheel; sprocket wheel to camshaft and sprocket wheel to drive shaft are all defined by dowel pins.

Fit sprocket wheel and drive shaft for radial piston pump on exhaust camshaft with timing chain attached.

Scheme 348

Tighten screws firmly down with special tool 11 3 470.

Fit open-end wrench to hex on intake camshaft.

Scheme 349

Rotate inlet camshaft with open-end wrench upwards from horizontal position until groove on camshaft guide bearing aligns with groove on 1st bearing cap.

Scheme 350

Attach special tool 11 5 080 in intake camshaft in such a way that special tool contacts timing case.

If necessary, align inlet camshaft.

Note. Intake camshaft remains secured with special tool 11 5 080 until end of adjustment work.

Scheme 351

Fit special tool 11 3 390 in place of chain tensioner piston.

Scheme 352

Preload bow cover with special tool 11 3 390 by turning adjusting screw with tool 00 2 050 or standard torque wrench with 1.3 Nm.

Scheme 353

Install guide for timing chain between intake and exhaust camshafts.

Scheme 354

Turn splined hub on VANOS gearbox clockwise as far as stop.

Scheme 355

Use grease to hold clutch on drive shaft for radial piston pump.

Scheme 356

Check gap "X" between VANOS case and splined shaft.

Specification X = 1 +/- 0.5 mm.

Replace O-rings.

Scheme 357

Push in splined shaft together with VANOS control unit so far that splines (1) are almost meshed with splined hub (2).

Note. Straight splines of splined shaft will already be meshed with intake camshaft.

Scheme 358

Check whether bevel splines of splined shaft (1) are precisely aligned "tooth to tooth gap" with splined hub (2).

Scheme 359

Special tool 11 3 490 must be used to install VANOS control unit in order to be able to adjust control diagram.

Scheme 360

Hold special tool 11 3 490 between VANOS control unit and face of timing case.

Push in VANOS control unit as far as timing case.

Note. Splined sleeve will be turned counterclockwise while pushing bevel splines (1) into splined sleeve (2).

Scheme 361

If bevel splines (1) cannot be pushed into splined hub (2), splined shaft and VANOS control unit must be pulled off far enough for it to be possible to turn splined shaft.

Scheme 362

Scheme 363

Select a new tooth position by turning splined shaft.

Repeat procedures until bevel splines mesh in splined sleeve.

Note. If necessary, repeat procedures several times.

Scheme 364

If correct position was found

Insert VANOS adjustment unit slowly and carefully with provided special tool 11 3 490.

Note. During installation, do not under any circumstance pull back the VANOS adjustment unit or push it on jerkily. This would cause the toothed shaft to slip out, thereby rendering the timing settings incorrect.

Note. When the VANOS adjustment unit is installed and the chain wheel screws tightened on the VANOS transmission, the special tool 11 3 490 must be inserted between the cylinder head and the VANOS adjustment unit.

Scheme 365

Tighten accessible chain wheel screws (at least two) on VANOS transmission to final torque of 10 Nm.

Remove special tool 11 5 080 from inlet camshaft.

Scheme 366

Remove special tool 11 2 300.

Scheme 367

Fit special tool 11 5 100 to four screws on crankshaft hub.

Scheme 368

Turn crankshaft further in direction of rotation until two other bolts of the sprocket on VANOS gearbox are accessible.

Tighten these two screws to final torque of 10 Nm.

Scheme 369

Turn crankshaft further in direction of rotation until last two bolts of sprocket on VANOS gearbox are accessible.

Tighten these two screws to final torque of 10 Nm.

Scheme 370

Remove special tool 11 3 490 between VANOS adjustment unit and face of timing case.

Scheme 371

Pull off VANOS control unit parallel to timing case far enough that O-rings are accessible.

Scheme 372

Clean and degrease sealing surfaces between end cover and timing case.

Apply thin and uniform coat of 3 Bond 1209 sealing compound.

Pay attention to dowel pins (1).

Scheme 373

Fit end cover to timing case and screw down tightly.

Scheme 374

Slide VANOS adjusting unit back up to timing case.

Scheme 375

Fit TDC sensor for cylinder recognition.

Scheme 376

Insert and tighten down screws 1 to 9.

Scheme 377

Turn engine twice in direction of engine rotation with special tool 11 5 100.

Scheme 378

Ensure that groove on thrust bearing on intake camshaft is aligned with groove on 1st bearing cover.

Scheme 379

Note. Due to technical revision, the dowel bore in the flywheel is discontinued from 9/93. The Parts Service will now only supply flywheels without dowel bores. Check firing TDC position of cylinder 1 on mark between vibration damper and underside of timing case cover.

Scheme 380

On flywheels produced before 9/93, secure crankshaft in TDC position with special tool 11 2 300.

Scheme 381

Check whether special tool 11 5 080 can be inserted in intake camshaft in such a way that it contacts timing case.

Remove special tool 11 5 080.

Scheme 382

Fit oil pipe to VANOS adjusting unit.

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Scheme 383

Loosen special tool 11 3 390 and remove.

Install chain tensioning piston, refer to 11 31 090 .

Adjust valve clearance, refer to 11 34 004 .

Assemble engine.

Scheme 384

11 31 019 Replacing all camshafts (S50 B32)

Remove bulkhead heater (air collector).

Remove fan clutch with fan cow. See 11 52 020 .

Remove connector strip for fuel injection valves (1), lift over fuel injection pipe and air lead and place to one side (2).

Scheme 385

Remove cylinder head cover.

Remove spark plugs.

Remove cover from plug connectors.

Scheme 386

Removal

Removal of the VANOS adjustment unit and the camshafts is described separately from installation. Assembly sequence for removal and installation is different.

Fit special tool 11 5 100 to four screws on crankshaft hub.

Scheme 387

Rotate crankshaft in direction of location as far as ignition TDC position of cylinder 1.

Secure vibration damper with special tool 11 2 300.

Scheme 388

Unscrew oil pipe from VANOS control unit.

Scheme 389

Fit special tool 11 7 350 to VANOS adjustment unit.

Connect up compressed air (2 ... 8 bar).

Scheme 390

Disconnect plug connection on solenoid valves on exhaust side.

Connect special tool 12 6 412 and special tool 12 6 410 to the solenoid valves on the exhaust end.

Connect special tool 12 6 410 to correct terminals on vehicle battery.

Press toggle switch on special tool 12 6 412 in direction of VANOS splined shaft and hold down.

Scheme 391

At the same time, brace exhaust camshaft on hex head against direction of location until groove in guide bearing is aligned with groove on first bearing cover.

Note. If necessary, press toggle switches on special tool 12 6 412 several times in both directions until camshaft starts to move.

Scheme 392

Disconnect plug connection of solenoid valves on intake end.

Connect special tool 12 6 412 to the solenoid valves on the intake end.

Press toggle switch on special tool 12 6 412 in direction of VANOS splined shaft and hold down.

Scheme 393

At the same time, rotate intake camshaft on hex head against direction of rotation until groove on guide bearing is aligned with groove of first bearing cover.

Note. If necessary, press toggle switches on special tool 12 6 412 several times in both directions until camshaft starts to move.

Scheme 394

Disconnect special tool 12 6 412 from the solenoid valves.

Disconnect compressed air.

Remove special tool 11 2 300.

Scheme 395

Remove chain guide from timing belt between intake and exhaust camshafts.

Scheme 396

Unfasten screws (1 ... 9) from VANOS adjustment unit.

Scheme 397

Unscrew end cover (VANOS bridge) on timing case.

Scheme 398

Scheme 399

Continue to rotate crankshaft in direction of rotation until the next two screws on the VANOS gear are accessible.

Unfasten these two screws.

Scheme 400

Now slacken the two screws accessible on the inlet end of the VANOS gear two turns.

Scheme 401

Continue to rotate crankshaft in direction of rotation until the next two screws on the VANOS gear are accessible.

Unfasten these two screws.

Scheme 402

Now slacken the two screws accessible on the inlet end of the VANOS gear two turns.

Scheme 403

Continue to rotate crankshaft in direction of rotation until cylinder 1 is in TDC position.

Secure vibration damper with special tool 11 2 300.

Scheme 404

Note. The grooves in guide bearings of exhaust and intake camshafts match the grooves in the 1st bearing cover.

Scheme 405

Now slacken the two screws accessible on the inlet end of the VANOS gear approx. two turns.

Scheme 406

Now slacken the two screws accessible on the inlet end of the VANOS gear two turns.

Scheme 407

Dismantle VANOS adjustment unit and remove.

Scheme 408

Scheme 409

Adjust intake camshaft on hex head approx. 10° in direction of rotation.

Scheme 410

Remove the two loosened screws on the intake end of the VANOS unit.

Scheme 411

Note. Do not tilt tooth hub during removal. Thrust washer and plate spring can drop out.

Carefully remove tooth hub from intake end and lift upwards to remove.

Scheme 412

Scheme 413

Grip split rings on inlet side with your fingers, carefully pull inlet chain wheel forwards and remove split rings from above.

Scheme 414

Remove intake sprocket from centering sleeve, extract from timing chain and lift out.

Scheme 415

Rotate intake camshaft inwards on hex head until cam tips on cylinder 1 are horizontal.

Scheme 416

Fit special tool 11 3 400 to intake camshaft and screw into spark plug threads of cylinders 2 and 5.

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Scheme 417

Preload intake camshaft by rotating eccentric shaft.

Unfasten all nuts for bearing cover on intake camshaft.

Scheme 418

Relieve tension on special tool 11 3 400 and remove.

Remove bearing cover and lift out intake camshaft.

Scheme 419

Turn exhaust camshaft inwards on hex head until cam tips are horizontal on cylinder 1.

Scheme 420

Fit special tool 11 3 400 to exhaust camshaft and screw into spark plug threads of cylinders 2 and 5.

Scheme 421

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Tighten exhaust camshaft by rotating eccentric shaft.

Unfasten all nuts on bearing cover for exhaust camshaft.

Scheme 422

Relieve tension on special tool 11 3 400 and remove.

Remove bearing cover and lift out exhaust shaft together with sprocket.

Secure timing chain to prevent it from sliding down.

Scheme 423

Installation of the VANOS adjustment unit and the camshafts is described separately from removal. Assembly sequence for removal and installation is different.

If necessary, replace VANOS gear, refer to 11 36 520 (S50 B32) .

Place timing chain on centering sleeve of intake camshaft.

Insert intake camshaft with centering sleeve in such a position that cams on cylinder 1 point horizontally inwards.

Scheme 424

Fit bearing covers.

Scheme 425

Fit special tool 11 3 400 to intake camshaft and screw into spark plug threads of cylinders 2 and 5.

Scheme 426

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Depress intake camshaft by rotating eccentric shaft.

Align bearing cover by hand until bearing cover and timing case are located over hollow dowels.

Fit nuts on bearing cover (intake camshaft) and tighten down.

Scheme 427

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Untighten and remove special tool.

Place timing chain on sprocket of exhaust camshaft.

Install exhaust camshaft and VANOS unit in such a way that cams on cylinder 1 point horizontally inwards.

Scheme 428

Fit bearing covers.

Scheme 429

Fit special tool 11 3 400 to exhaust camshaft and screw into spark plug threads of cylinders 2 and 5.

Scheme 430

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Depress exhaust shaft by rotating eccentric shaft.

Align bearing cover by hand until bearing cover and timing case are located over hollow dowels.

Fit nuts to bearing cover on exhaust

camshaft and tighten down.

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Untighten and remove special tool.

Scheme 431

Rotate exhaust camshaft upwards from horizontal position on hex head until groove in guide bearing is aligned with groove in 1st bearing cover.

Scheme 432

Rotate intake camshaft on hex head from horizontal position in direction of rotation to approx. 10° position.

Scheme 433

Brace timing chain on intake end and position sprocket of timing chain on exhaust end

1. For the spline hub right stop, the screws of the must be positioned at least one half and at the quarters behind the blades of the impeller.
2. The left screw head side must be visible.

Scheme 434

Brace timing chain and do not alter position.

Insert intake sprocket in timing chain and place on sleeve of intake camshaft

1. Centre of one half of long hole is aligned with timing case.

Scheme 435

Note. Position of long hole on intake sprocket is only for access to screws. It does not affect function

Fit half rings to intake side with flat side facing sprocket.

Scheme 436

Note. Plate spring (2) points towards thrust washer with small locating diameter (3). Thrust washer is guided into tooth hub by its retaining lugs.

Insert plate spring (2) and thrust washer (3) in tooth hub (1).

Scheme 437

Carefully insert tooth hub and plate spring with thrust washer on intake end from above and place on centering sleeve.

Scheme 438

Turn the half-rings in such a way that when the tooth hub is being fitted the screws can be inserted in the threads (1) first.

Keep to the other assembly sequence (2 and 3).

Scheme 439

Secure toothed hub with two screws. Fit screws without clearance but do not tighten.

Scheme 440

Install chain tensioning piston, refer to 11 31 090 .

Scheme 441

Fit special tool 11 7 341/342 to intake camshaft.

Turn intake camshaft on hex head away from 10° setting until special tool 11 7 341 fits flush against timing case.

Scheme 442

Fit special tool 11 7 342 into exhaust camshaft.

Align exhaust camshaft on hex head with special tool 11 7 341 flush against timing case.

Remove special tool 11 7 341 / 342.

Scheme 443

Fit special tool 11 7 350 to VANOS adjustment unit.

Connect up compressed air (2 ... 8 bar).

Scheme 444

Check switching operation of solenoid valves

Connect special tools 12 6 412 and 12 6 410 to the solenoid valves on the exhaust end.

Connect special tool 12 6 410 to correct terminals on vehicle battery.

Press toggle switch on special tool 12 6 412 to extend VANOS splined shaft.

Splined shaft extends with hydraulic piston.

Scheme 445

Press toggle switch on special tool 12 6 412 into position for retracting VANOS splined shaft.

Splined shaft retracts on hydraulic piston (initial setting).

Scheme 446

Connect special tool 12 6 412 to plug connection of solenoid valves on intake end.

Press toggle switch on special tool 12 6 412 to extend VANOS splined shaft.

Splined shaft extends with hydraulic piston.

Scheme 447

Press toggle switch on special tool 12 6 412 into position for retracting VANOS splined shaft.

Splined shaft retracts on hydraulic piston (initial setting).

Scheme 448

Disconnect compressed air.

Remove special tool 11 7 350.

Scheme 449

Press toggle switch on special tool 12 6 412 into position for retracting VANOS splined shaft.

Hydraulic piston is vented.

At the same time, press splined shaft and hydraulic piston back into initial position by hand.

Scheme 450

Connect special tool 12 6 412 to the solenoid valves on the exhaust end.

Press toggle switch on special tool 12 6 412 into position for retracting VANOS splined shaft.

Hydraulic piston is vented.

At the same time, press splined shaft and hydraulic piston back into initial position by hand.

Scheme 451

Disconnect special tools 12 6 412 and 12 6 410 from the solenoid valves.

Replace sealing rings.

Scheme 452

Turn splined hubs on intake and exhaust camshafts to right limit position.

Scheme 453

Insert VANOS adjustment unit with splined shaft on exhaust end into VANOS gear until helical gear (1) almost locates in splined hub (2).

Scheme 454

Note. Spur gear on splined shaft is already in mesh with the exhaust camshaft.

Check whether bevel splines of splined shaft (1) are precisely aligned "tooth to tooth gap" with splined hub (2).

If it proves impossible to insert the physical gear in the splined hub, retract VANOS adjustment unit with splined shaft until spline can rotate freely.

Scheme 455

Select a new tooth position by turning splined shaft.

Scheme 456

Repeat operation until helical gear engages in splined hub.

Repeat procedure on the intake end.

On the exhaust end, align radial piston pump with driver on splined hub.

Scheme 457

Insert VANOS adjustment unit as far as timing case and secure to timing case with two screws.

Scheme 458

Tighten down two accessible screws on inlet end of VANOS gear to 10 Nm.

Scheme 459

Tighten down two accessible screws on exhaust end of VANOS gear to 10 Nm.

Scheme 460

Remove special tool 11 2 300.

Scheme 461

Fit special tool 11 5 100 to four screws on crankshaft hub.

Scheme 462

Continue rotating crankshaft in direction of rotation until two more screws are accessible on the intake end of the VANOS unit.

Insert these two screws and tighten down to 10 Nm.

Scheme 463

Tighten down two accessible screws on exhaust end of VANOS gear to 10 Nm.

Scheme 464

Continue to rotate crankshaft in direction of rotation until remaining two screws on intake end of VANOS unit are accessible.

Insert these two screws and tighten down to 10 Nm.

Scheme 465

Tighten down last two screws on exhaust end of VANOS gear to 10 Nm.

Scheme 466

Rotate crankshaft in direction of location as far as ignition TDC position of cylinder 1.

Secure vibration damper with special tool 11 2 300.

Scheme 467

Ensure that grooves in pilot bearings of exhaust and intake camshafts are aligned with grooves in 1st bearing covers.

Scheme 468

Check whether special tool 11 5 080 can be inserted in intake camshaft flush with timing case.

Scheme 469

Check whether special tool 11 5 080 can be inserted in exhaust camshaft flush with timing case.

Remove special tool 11 5 080.

Remove special tool 11 2 300.

Scheme 470

Install chain guide of timing chain between intake and exhaust camshafts.

Scheme 471

Unfasten screw on VANOS adjustment unit and retract VANOS adjustment unit from timing case until O-rings are exposed.

Scheme 472

Clean and degrease sealing surfaces between end cover and timing case.

Apply thin, uniform coat of Drei Bond 1209 sealing agent.

Pay attention to dowel pins (1).

Scheme 473

Fit end cover (VANOS bridge) to timing case and tighten down.

Scheme 474

Push in VANOS control unit as far as timing case.

Scheme 475

Note. Secure ground tape with screw (7).

Insert screws (1 ... 9) in VANOS adjustment unit and tighten down in two passes.

Scheme 476

Insert screw connections in solenoid valves.

Fit cover to plug connections.

Scheme 477

Fit oil pipe to VANOS adjusting unit.

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Adjust valve clearance, refer to 11 34 004 .

Assemble engine.

Scheme 478

S50 B30

Unfasten screw connection for chain tensioner.

Remove chain tensioner piston together with spring.

Scheme 479

Arrangement of components

1. Screw plug
2. Sealing ring
3. Spring
4. Chain tensioner piston

Scheme 480

Install chain tensioner piston (4) with vent groove facing upwards and guide lugs locating in clamping rail.

Install spring (3) with tapered end pointing towards screw plug.

Scheme 481

Replace seal (2) and tighten down seal screw (1).

Tightening torque, refer to TIGHTENING SPECIFICATIONS .

Scheme 482

Unfasten screw plug and remove hydraulic chain tensioner.

Scheme 483

If a hydraulic chain tensioner is reused, the oil chamber in the tensioner unit must first be drained.

Place hydraulic chain tensioner on level base and carefully compress.

Repeat this procedure twice.

Scheme 484

Replace sealing ring (3).

Insert hydraulic chain tensioner (1) in cylinder for chain tensioner piston (2) and engage guide lugs in clamping rail.

Insert cylinder for chain tensioner piston and tighten down.

Tightening torque

refer to TIGHTENING SPECIFICATIONS .

Scheme 485

11 31 505 Adjusting timing of camshafts (S50 B32)

Scheme 486

Note. If a fault is identified during the preliminary work of checking camshaft timing, remove the VANOS adjustment unit and readjust the camshafts.

Note. The engine is at the TDC firing position of the first cylinder. The cam tips of the exhaust and intake camshafts point to each other. The grooves in the exhaust and intake camshafts point to the grooves in the first bearing cover.

Scheme 487

Remove special tool 11 2 300.

Scheme 488

Unfasten screws (1 ... 9) from VANOS adjustment unit.

Scheme 489

Unscrew end cover (VANOS bridge) on timing case.

Scheme 490

Scheme 491

Continue to rotate crankshaft in direction of rotation until the next two screws on the VANOS gear are accessible.

Now unfasten the two screws accessible on the intake end of the VANOS gear approx. two complete turns.

Scheme 492

Now unfasten the two screws accessible on the exhaust end of the VANOS gear approx. two complete turns.

Scheme 493

Continue to rotate crankshaft in direction of rotation until the next two screws on the VANOS gear are accessible.

Now unfasten the two screws accessible on the intake end of the VANOS gear approx. two complete turns.

Scheme 494

Now unfasten the two screws accessible on the exhaust end of the VANOS gear approx. two complete turns.

Scheme 495

Turn engine in direction of rotation as far as TDC firing position of first cylinder.

Secure vibration damper with special tool 11 2 300.

Scheme 496

Note. The cam tips of the exhaust and intake camshafts point to each other. The grooves in the exhaust and intake camshafts point to the grooves in the first bearing cover.

Scheme 497

Now unfasten the two screws accessible on the intake end of the VANOS gear approx. two complete turns.

Scheme 498

Now unfasten the two screws accessible on the exhaust end of the VANOS gear approx. two complete turns.

Scheme 499

Dismantle VANOS adjustment unit and remove.

Scheme 500

Scheme 501

Fit special tool 11 7 341 / 342 to intake camshaft.

Align intake camshaft at hex head until special tool 11 7 341 is flush against timing case.

Scheme 502

Insert special tool 11 7 342 into exhaust camshaft.

Align exhaust camshaft at hex head until special tool 11 7 341 is flush against timing case.

Remove special tool 11 7 341 / 342.

Scheme 503

Fit special tool 11 7 350 to the removed VANOS adjustment unit.

Scheme 504

Connect up compressed air (2 ... 8 bar).

Check switching operation of solenoid valves

Connect special tools 12 6 412 and 12 6 410 to the solenoid valves on the exhaust end.

Connect special tool 12 6 410 to correct terminals on vehicle battery.

Scheme 505

Press toggle switch on special tool 12 6 412 to extend VANOS splined shaft.

Splined shaft extends with hydraulic piston.

Press toggle switch on special tool 12 6 412 into position for retracting VANOS splined shaft.

Splined shaft retracts on hydraulic piston (initial setting).

Scheme 506

Connect special tool 12 6 412 to plug connection for solenoid valves on intake end.

Press toggle switch on special tool 12 6 412 to extend VANOS splined shaft.

Splined shaft extends with hydraulic piston.

Scheme 507

Press toggle switch on special tool 12 6 412 into position for retracting VANOS splined shaft.

Splined shaft retracts on hydraulic piston (initial setting).

Scheme 508

Disconnect compressed air.

Remove special tool 11 7 350.

Scheme 509

Press toggle switch on special tool 12 6 412 into position for retracting VANOS splined shaft.

Hydraulic piston is vented.

At the same time, press splined shaft and hydraulic piston back into initial position by hand.

Scheme 510

Connect special tool 12 6 412 to the solenoid valves on the exhaust end.

Press toggle switch on special tool 12 6 412 into position for retracting VANOS splined shaft.

Hydraulic piston is vented.

At the same time, press splined shaft and hydraulic piston back into initial position by hand.

Scheme 511

Disconnect special tools 12 6 412 and 12 6 410 from the solenoid valves.

Replace sealing rings.

Scheme 512

Turn splined hubs on intake and exhaust camshafts to right limit position.

Scheme 513

Note. On right detent of tooth hub, screws on VANOS- gear must be at least half and no more than three quarters below vanes on impeller. Left side of screw head can be seen. If this position is not reached, the screw heads are no longer accessible after installation of the VANOS adjustment unit; if necessary, remove and reposition chain wheel. This task is described in the work step dealing with replacing camshafts, refer to 11 31 019 (S50 B32)

Scheme 514

Insert VANOS adjustment unit with splined shaft on exhaust end into VANOS gear until helical gear (1) almost locates in splined hub (2).

Note. Spur gear on splined shaft is already in mesh with the exhaust camshaft.

Scheme 515

Check whether bevel splines of splined shaft (1) are precisely aligned "tooth to tooth gap" with splined hub (2).

If it proves impossible to insert the physical gear in the splined hub, retract VANOS adjustment unit with splined shaft until spline can rotate freely.

Scheme 516

Select a new tooth position by turning splined shaft.

Scheme 517

Repeat operation until helical gear engages in splined hub.

Repeat procedure on the intake end.

Note. The splined shaft on the intake end is always approx. 5 mm shorter. If a new spline setting has to be sought on the intake end, retract VANOS adjustment unit just far enough to leave exhaust end in mesh.

On the exhaust end, align radial piston pump with driver on splined hub.

Scheme 518

Insert VANOS adjustment unit as far as timing case and secure to timing case with two screws.

Scheme 519

Tighten down the accessible two screws on the intake end of the VANOS unit.

Scheme 520

Tighten down the two accessible screws on the exhaust end of the VANOS unit.

Scheme 521

Remove special tool 11 2 300.

Scheme 522

Fit special tool 11 5 100 to four screws on crankshaft hub.

Scheme 523

Continue rotating crankshaft in direction of rotation until two more screws are accessible on the intake end of the VANOS unit.

Tighten these two bolts.

Scheme 524

Tighten down the two accessible screws on the exhaust end of the VANOS unit.

Scheme 525

Continue to rotate crankshaft in direction of rotation until remaining two screws on intake end of VANOS unit are accessible.

Tighten these two bolts.

Scheme 526

Tighten down the last two screws on the exhaust end of the VANOS unit.

Scheme 527

Turn engine in direction of rotation as far as TDC firing position of first cylinder.

Secure vibration damper with special tool 11 2 300.

Scheme 528

Note. The grooves in the exhaust and intake camshafts are aligned with the grooves in the first bearing covers. The cam tips of the exhaust and intake camshafts point to each other.

Scheme 529

Note. Check camshaft adjustment with special tool 11 5 080.

Special tool 11 5 080 inserted into intake camshaft.

Special tool 11 5 080 must rest on the timing case without a gap.

Scheme 530

Note. Check camshaft adjustment with special tool 11 5 080.

Special tool 11 5 080 inserted into exhaust camshaft.

Special tool 11 5 080 must rest on the timing case without a gap.

Remove special tool 11 5 080.

Scheme 531

Remove special tool 11 2 300.

Scheme 532

Unfasten screws on VANOS adjustment unit and retract VANOS adjustment unit from timing case until O-rings are exposed.

Scheme 533

Clean and degrease sealing surfaces between end cover and timing case.

Apply thin and uniform coat of 3 Bond 1209 sealing compound.

Pay attention to dowel pins (1).

Scheme 534

Fit end cover (VANOS bridge) to timing case and tighten down.

Scheme 535

Push in VANOS control unit as far as timing case.

Scheme 536

Note. Secure ground tape with screw (7).

Install screws (1 ... 9) of VANOS adjustment unit, pretighten to approx. 5 Nm and then tighten securely in a second tightening procedure.

Scheme 537

Insert screw connections in solenoid valves.

Fit cover to plug connections.

Scheme 538

Fit oil pipe to VANOS adjusting unit.

Tightening Torque, refer to TIGHTENING SPECIFICATIONS .

Assemble engine.

Scheme 539

12 14 530 Replacing sensor for intake camshaft (S50)

Switch off ignition.

Disconnect connector (2).

Scheme 540

Release screw from pulse generator.

Remove sensor.

Check seal for damage, replacing if necessary.

Scheme 541

12 14 535 Replacing sensor for outlet camshaft (S50)

Switch off ignition.

Release screws and remove cover.

Scheme 542

Disconnect connector (2).

Scheme 543

Release screw from pulse generator.

Remove sensor.

Scheme 544

Check seal for damage, replacing if necessary.

Interrogate fault memory of DME-control unit, check faults stored in memory, rectify faults then cancel fault memory.

12 14 560 Replacing control module (VANOS) (S50 B30)

Read fault memory.

Switch off ignition.

Remove container for intensive cleaning fluid (1) and place to one side.

Remove coolant expansion container (2) and place to one side.

Note. Coolant hoses remain connected.

Scheme 545

Remove soundproofing sheet.

Scheme 546

Release screws and remove cover.

Fit rubber grommets to apertures to positive battery lead, correctly aligned with apertures (1) and (2).

No water leaks!

Scheme 547

Localize VANOS control unit (1).

Scheme 548

Pull control unit and holder in downwards direction.

Disconnect connector.

Pull control unit and holder in forwards direction.

Scheme 549

Interrogate fault memory of DME and VANOS control modules, check fault messages stored memory, rectify these faults and clear the fault memory.

Scheme 550

11 34 004 Checking valve clearance (S50)

Remove and install cylinder-head cover

Remove and install fan shroud

Remove and install spark plugs

Use Special Tool 11 5 100 to rotate crankshaft.

Scheme 551

Fit Special Tool 11 5 100 on four screws on crankshaft hub and turn engine.

Scheme 552

Measure valve clearance with cams pointing upwards.

Scheme 553

If measured valve clearance exceeds specified valve-clearance tolerance, rotate recesses in bucket tappets as shown in picture.

Scheme 554

Insert Special Tool 11 5 070 between two upwards-facing cams and press bucket tappets downwards.

Scheme 555

Blow clean valve-adjustment plate with compressed air.

Scheme 556

Measure removed valve-adjustment plate.

Fit requisite adjustment plate with lettering to underside.

Scheme 557

11 34 552 Removing and installing or replacing all valves - cylinder head removed (S50)

Preliminary tasks are described in Disassembling and assembling cylinder head.

Replace valve stem seals.

Remove valves from cylinder head.

If necessary, check valve guide for wear.

If necessary, remachine valve seat.

Scheme 558

Installation sequence

1. Valve
2. Valve-stem seal
3. Lower plate spring
4. Outer spring
5. Inner spring
6. Top plate spring
7. Valve tapers

11 34 560 Replacing all valve stem seals - cylinder head removed (S50 / S54)

Special tools required

1. 11 1 200
2. 11 1 380
3. 11 1 480
4. 11 1 960

Preliminary tasks are described in Disassembling and assembling cylinder head.

Remove valve stem seal with special tool 11 1 480.

Scheme 559

Valve stem diameter 7 mm

Installation

Lubricate valve stem with oil and insert valve.

Fit special tool 11 1 380.

Coat new valve stem seal (1) with oil and install.

Scheme 560

S50 B32 and S54

Valve stem diameter 6 mm

Installation

Lubricate valve stem with oil and insert valve.

Fit special tool 11 1 960.

Coat new valve stem seal (1) with oil and install.

Scheme 561

Note. Special tool 11 1 200 is used for valve stem diameters 6 mm and 7 mm.

Installation

Press valve stem seal firmly home by hand with special tool 11 1 200.

Scheme 562

11 34 715 Replacing all valve springs - cylinder removed (S50)

Special tools required

1. 11 0 194
2. 11 0 342

Preliminary tasks are described in Disassembling and assembling cylinder head.

Align special tool 11 0 194 in direction of valve shaft and select appropriate groove in special tool 11 0 342.

Scheme 563

Press down valve spring on spring cap, top, and remove valve keys.

Remove valve spring and plate spring.

Scheme 564

Note. In event of damage to an inner or outer spring

replace inner and outer valve springs.

1. Valve
2. Valve-stem seal
3. Lower plate spring
4. Outer spring
5. Inner spring
6. Top plate spring
7. Valve tapers

Scheme 565

General

VANOS has the task of adjusting the spread of the intake camshaft in a variable manner from advance to retard and vice versa.

Opening and closing times for intake camshaft are adjusted between advance and retard in a parallel fashion.

The VANOS system is controlled by a dedicated VANOS control unit which is connected by CAN (Controller Area Network) to DME (Digital Engine Electronics) M3.3.

In contrast to M50 VANOS, this adjustment is an infinitely variable process.

Governed maximum speed of 250 km/h is also controlled by VANOS adjustment unit.

Development of this system achieved following objectives

1. Increase in torque in central speed range, increased performance in higher speed range by extended timing intervals
2. Less unburnt residual gases at idle speed achieved with smaller spread, thereby improving idle characteristics.
3. Catalytic converter reaches operating temperature faster after cold starts
4. Reduction of fuel consumption

Operation

VANOS housing contains VANOS compressed-oil pump, two solenoid valves and adjustment cylinder.

The VANOS control unit determines the optimum position for the intake camshaft from the throttle valve position signal and the engine speed. Continuous sensing of notched gears by sensors checks the relative angle setting between the intake camshaft (adjustable shaft) and exhaust camshaft (reference shaft), compares this with the specified nominal value and, when required, energizes the solenoid valves.

Adjustment of intake camshaft is performed by a control piston which is connected to an adjustable splined shaft.

The camshaft and sprocket wheel with integral actuator transmission are connected by splined shaft.

When control piston is displaced, splined shaft in actuator transmission rotates camshaft relative to sprocket wheel.

Oil pressure required for adjustment is generated by VANOS compressed-oil pump (radial piston pump).

Function of VANOS hydraulic system

Engine oil pump carries oil to VANOS compressed-oil pump. This pump is driven by exhaust camshaft and develops continuous pressure of 100 bar To develop pressure immediately when a solenoid valve opens, hydraulic system is equipped with an oil accumulator.

If a calculation in VANOS control unit calls for a retard adjustment to intake camshaft, solenoid valve 1 remains closed and solenoid valve 2 opens.

Note. Valves are closed when de-energized.

This means that oil pressure is only developed on reverse side of piston. Control piston in adjustment cylinder moves in direction of travel and splined shaft rotates camshaft in its retard direction.

When engine is started, initially both solenoid valves are closed. Immediately after start, VANOS control unit decides whether camshaft adjustment is actually necessary.

At idle speed, intake camshaft points towards its retard setting.

If a calculation in VANOS control unit shows that an adjustment in advance setting is required (e.g. full throttle from central speed range), solenoid valve 1 is opened and solenoid valve 2 remains closed. Control piston in adjustment cylinder moves in direction of travel and splined shaft rotates intake camshaft in its advance direction.

Once calculated adjustment is terminated, both solenoid valves close and camshaft remains in setting it has reached.

Function of VANOS electrical system

VANOS control unit uses sensor 1 (exhaust camshaft) and sensor 2 (intake camshaft) in conjunction with notched wheels to determine current setting of the camshaft. Required setting of intake camshaft is calculated from engine-speed signal and throttle-valve position signal.

This setting is stored in a characteristics file. If nominal and actual values deviate from one another, an appropriate correction is made.

VANOS control unit is capable of diagnosis work.

Using a BMW Service Tester or MoDiC, the non-volatile fault memory can be interrogated.

11 36 010 Removing and installing, sealing/replacing VANOS adjustment unit (S50 B30)

Interrogate fault memory and make a documentary record.

Remove cylinder head cover.

Remove fan clutch with fan impeller and fan cowl, refer to 11 52 020 .

If necessary, replace filter screw on VANOS adjustment unit.

Tightening Torque, refer to TIGHTENING SPECIFICATIONS . .

Scheme 566

Removal

Removal of VANOS adjustment unit is described separately from installation.

Assembly sequence for removal and installation is different.

Remove cover from plug connectors.

Disconnect plug connections on solenoid valves.

Scheme 567

Unscrew oil pipe from VANOS control unit.

Scheme 568

Unscrew cover bolts.

Scheme 569

Remove cover. Collar nut is accessible.

Scheme 570

Grip shaft with a hexagon socket. Release collar nut with a ring wrench.

Scheme 571

Note. Only the use of an exactly fitting hexagon nut will prevent the hexagon from being damaged and the shaft from being bent.

Remove TDC sensor for cylinder identification.

Scheme 572

Unfasten screws on VANOS adjustment unit.

Scheme 573

Unscrew end cover (VANOS bridge) on timing case.

Scheme 574

Scheme 575

Pull off VANOS control unit.

Note. Splined shaft remains in VANOS unit on engine.

Scheme 576

Installation of VANOS adjustment unit is described separately from removal.

Assembly sequence differs between removal and installation.

Replace O-rings on VANOS adjustment unit and splined shaft.

Fit driver of radial piston pump to drive shaft using grease as an aid.

Align radial piston pump on driver.

Slide on VANOS adjustment unit until sealing rings are still just accessible.

Scheme 577

Clean and degrease sealing faces between end cover (VANOS bridge) and timing case.

Apply thin and uniform coat of Drei Bond 1209 sealing compound.

Pay attention to dowel pins (1).