4.9l 6-cyl - VIN [y] Ford Cab & Chassis Ranger

ENGINE IDENTIFICATION

Note. For engine repair procedures not covered in this article, see ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION article in the GENERAL INFORMATION section.

Engine is identified by the eighth character of Vehicle Identification Number (VIN). VIN is visible through windshield on left upper side of instrument panel. VIN is also located on Safety Compliance Certification Label, attached to left door lock pillar.

ENGINE IDENTIFICATION CODES

Scheme 27

1. Positive stop rocker arm bolts are used to eliminate valve clearance adjustments. Valve stem-to-rocker arm clearance is measured with lifter collapsed. To obtain correct valve clearance after machine work is done,.060" (1.52 mm) undersize or.060" (1.52 mm) oversize push rod may be used.
2. With ignition switch in "OFF" position, use remote starter switch to turn crankshaft. Rotate crankshaft until No. 1 piston is at TDC of compression stroke. Mark timing mark on vibration damper with chalk, then make 2 additional chalk marks on vibration damper, spaced approximately 120° apart. (Scheme 27) (Scheme 27): Marking Vibration Damper for Valve Clearance Adjustment Space chalk marks approximately 120 degrees apart.
3. Slowly collapse lifter plunger until completely bottomed, using Lifter Compressor (T70P-6513-A). While maintaining pressure on lifter, use feeler gauge to check clearance between rocker arm and valve stem tip. Desired clearance is.125-.175" (3.18-4.45 mm). Allowable range is.100-.200" (2.54-5.08 mm).
4. If clearance is less than specifications, install shorter push rod. If clearance is greater than specifications, install longer push rod. Rotate crankshaft 120° (in direction of normal rotation) to adjust next set of valves in firing order sequence. Firing order is 1-5-3-6-2-4. Repeat procedure for remaining valves.

ENGINE REMOVAL

See ENGINE REMOVAL article in the ENGINE section.

Removal

1. Remove air cleaner. Disconnect accelerator cable or rod at carburetor. Remove accelerator return spring. Remove kickdown rod return spring (vehicles with automatic transmission). Remove accelerator rod bellcrank assembly.
2. Label and disconnect all vacuum lines at carburetor. Disconnect fuel inlet line at carburetor. Disconnect carburetor feedback solenoid and choke electric assist connectors. Disconnect header pipe from exhaust manifold. Disconnect power brake vacuum line (if equipped).
3. Remove crankcase vent hose from intake manifold. Remove manifolds from cylinder head. Separate manifolds by removing nuts securing manifolds together. Discard all gaskets.

Installation

Note. DO NOT use combination intake/exhaust gasket if installing new exhaust manifold.

Scheme 28

1. Clean mating surfaces of cylinder head and manifolds. If only one manifold is to be replaced, transfer tube fittings and install new studs. Lightly coat intake and exhaust manifold mating surfaces with graphite grease. Using new gasket, position exhaust manifold over studs of intake manifold.
2. Install lock washers, and tighten nuts finger tight. Coat manifold assembly and cylinder head mating surfaces lightly with graphite grease. Using new gasket, install and tighten intake manifold. Ensure gaskets have not become dislodged. Tighten nuts securing manifolds together. (Scheme 28) (Scheme 28): Intake & Exhaust Manifold Tightening Sequence Tighten to 22-32 ft. lbs. (30-43 N.m).
3. Using new gaskets as required, install remaining components in reverse order of removal. Adjust linkage and carburetor.

CYLINDER HEAD

1. Drain cooling system and remove air cleaner. Remove PCV valve and carburetor fuel inlet line. Disconnect vent hose at intake manifold. Label and remove all vacuum lines at carburetor.
2. Remove accelerator cable return spring and disconnect accelerator cable from carburetor. On vehicles with automatic transmission, disconnect kickdown rod at carburetor. Disconnect Electronic Engine Control (EEC) harness from all sensors, if equipped.
3. Disconnect upper radiator hose and heater hose at coolant outlet elbow. Remove coil bracket retaining bolt, and position coil to one side. Disconnect exhaust pipe from manifold. Remove rocker arm cover. Loosen rocker arm bolts, and rotate rocker arms to one side.
4. Identify push rods for reinstallation in original locations and remove. Disconnect spark plug wires at spark plugs. Remove cylinder head bolts and attach lifting eyes to cylinder head. Using engine hoist and lifting sling, raise cylinder head and manifold assembly from engine.

1. Clean all gasket mating surfaces. Check block and head gasket surfaces for warpage. Position new gasket over dowel pins on cylinder block. Install lifting eyes on cylinder head (in same locations as used to detach head assembly). Using lifting device, position cylinder head over block.
2. Carefully lower head assembly onto block. Ensure dowel pins properly engage in head. Remove hoist and lifting eyes. Coat threads of head bolts with engine oil and install. Tighten head bolts in sequence using 3 steps. (Scheme 29)
3. Lubricate push rod ends, rocker arm fulcrum seats and sockets with polyethylene grease and install. Reverse removal procedure to complete installation.

Cylinder Head Tightening Sequence Tighten bolts in 3 steps. Scheme 29

Front-to-Rear

E-I-E-I-E-I-E-I-E-I-E-I.

1. Remove air cleaner. Remove accelerator cable return spring and disconnect accelerator cable at carburetor. Remove PCV valve from rocker arm cover. Remove rocker arm cover.
2. Remove spark plug from cylinder to be serviced. Crank engine to position piston at TDC on compression stroke. Install an air hose and adapter to spark plug hole and apply air pressure. DO NOT remove air pressure until all valve components are reinstalled.
3. Remove rocker arm bolt, fulcrum seat, rocker arm, fulcrum guide and push rod. Reinstall bolt. Using valve spring compressor, compress spring and remove retainer locks. Remove spring retainer, spring and oil seal.

Valve Assembly for 4.9L Engine Install springs with tighter coils downward. Scheme 30

Inspection

1. Inspect valve stem for wear and binding in valve guide. Using valve spring tester, check valve spring tension. Replace springs that fail to meet specifications.
2. Using steel square and flat surface, measure gap between top of coil of spring and square, while slowly rotating spring. Replace spring if out-of-square more than.078" (1.98 mm). (Scheme 31)

Checking Valve Spring Squareness Measure gap while slowly rotating spring. Scheme 31

1. Lubricate valve stem with heavy engine oil. Install new valve stem oil seal. Install spring with closed coil end downward. Install spring retainer, and compress spring to install retainer locks.
2. Apply polyethylene grease to both ends of push rod, top of valve stem, fulcrum seat and socket. Install push rod, rocker arm, fulcrum seat and retaining bolt. Check the valve clearance. Refer to «VALVE CLEARANCE ADJUSTMENT»(/ford/cab-chassis-ranger/1985-1986/remont/mechanical/#49l-6-cyl-vin-y) in this article.
3. Remove air hose and adapter. Install spark plug. Reverse removal procedure to install remaining components.

VALVE SPRING INSTALLED HEIGHT

Scheme 32

1. Using dividers and scale, measure assembled height of valve spring from surface of cylinder head spring pad to underside of spring retainer. (Scheme 32) (Scheme 32): Checking Valve Spring Installed Height Do not install spacers unless necessary.
2. If spring height is excessive, install necessary.030" (.76 mm) spacer(s) between cylinder head spring pad and valve spring to correct height.

SPRING LENGTH SPECIFICATIONS

VALVE SPRING INSTALLED HEIGHT SPECIFICATIONS

VALVE STEM OIL SEALS

Cup-type Teflon oil seals are used on valves. Install cupped side down over valve stem. Use procedure described in VALVE SPRINGS to replace seals.

VALVE GUIDE SERVICING

When reaming valve guides, always use reamers in proper size sequence, from smallest to largest. Reface valve seats after reaming operation. Use scraper to break sharp corner at top of valve guide bore after reaming. (Scheme 33) Replacement valves are available in.003" (.08 mm),.015" (.38 mm) and.030" (.76 mm) oversize.

Reaming Valve Guides Always use reamers in proper size sequence. Scheme 33

Scheme 34

1. Lifters should be serviced as complete assemblies only. Lifters must be disassembled and cleaned prior to testing, and must be tested using hydraulic lifter testing fluid. Test cannot be performed with engine oil in lifters. Lifter components are select fit and are not interchangeable. (Scheme 34) (Scheme 34): Hydraulic Lifter Assembly Do not interchange components between lifters.
2. Leak-down rate on all lifters is 10-50 seconds at 1/16" (1.6 mm) plunger travel, using lifter leak-down tester. Specification is for amount of time required for plunger to leak-down under 50 lb. load with testing fluid in lifter. Replace lifter assembly if range specified is exceeded.

1. Drain crankcase and cooling system. Remove radiator and shroud. Remove alternator adjusting arm bolt, and swing arm to side.
2. Remove fan, drive belts, spacer and pulleys. Remove vibration damper. Remove oil pan front bolts and front cover attaching bolts. Remove front cover and gasket.

1. Cut front oil pan seal flush with cylinder block/pan junction. Remove seal. Clean all gasket mating surfaces. Cut and fit new pan seal. Seal must fit flush with cylinder block/pan junction.
2. Coat cylinder block and front cover gasket surfaces with oil resistant sealer. Install front cover gasket. Apply silicone sealer to junction of block and pan. Lubricate front cover oil seal.
3. Position front cover in place. Start front cover and pan attaching bolts. Slide Front Cover Aligner (T68P-6019-A) over crankshaft and into seal bore.
4. Install alternator adjusting arm. Tighten the oil pan bolts first, then tighten front cover bolts. Remove the Aligner. Reverse removal procedure to complete installation.

With front cover removed from engine, drive oil seal out of cover using pin punch. Clean out seal recess in front cover.

Lubricate new seal. Drive in seal with Installer (T68P-6700-A) until seal is fully seated in front cover recess. Check seal after installation to ensure spring is properly positioned in seal. Install front cover. (Scheme 35)

Installing Front Cover Oil Seal Fully seat seal in front cover recess. Scheme 35

TIMING GEARS

Scheme 36

1. Remove engine front cover. Make 6 chalk marks on camshaft gear, about 60° apart. Attach dial indicator to front of cylinder block. (Scheme 36) (Scheme 36): Checking Timing Gear Backlash Backlash should be.004-.010 (.10-.25 mm).
2. Using dial indicator to measure amount of gear backlash, take measurements at each of 6 chalk marks on camshaft gear.
3. To obtain an accurate reading, hold gear firmly against block. Backlash should be.004-.010" (.10-.25 mm). If any reading is not within limits, replace timing gears as set.

Drain cooling system and crankcase. Remove engine front cover and oil slinger. Align camshaft and crankshaft gear timing marks. (Scheme 37) Use gear puller to remove camshaft and crankshaft gears.

Aligning Timing Marks Use gear puller to remove gears. Scheme 37

1. Ensure camshaft key spacer and thrust plate are correctly installed. Align both gear keyways with respective keys, and press on gears using Gear Installer (T65L-6306-A).
2. Ensure that timing marks on camshaft and crankshaft gears are still aligned. Install front cover and related components.

1. Drain cooling system and crankcase. Remove radiator and shroud. Identify lifters for reassembly in original locations, then remove lifters. Remove front cover.
2. Disconnect fuel lines at fuel pump and remove pump. Disconnect vacuum hose and wires to distributor, and remove distributor.
3. Turn crankshaft to align gear timing marks. Remove camshaft thrust plate bolts, gear, key, thrust plate and spacer. Remove camshaft, taking care not to damage camshaft lobes or bearings.

1. Coat camshaft lobes with polyethylene grease and coat journals with engine oil. Assemble key, spacer and thrust plate to camshaft. Align gear keyway with key and install gear.
2. Install the camshaft, gear and thrust plate as an assembly. With timing marks aligned, tighten thrust plate attaching bolts. Replace front cover oil seal. Reverse removal procedure to complete installation, using new gaskets.

Camshaft Assembly Install camshaft, gear and thrust plate as an assembly. Scheme 38

CAMSHAFT END PLAY

1. Remove engine front cover. Loosen rocker arms. Push camshaft rearward into engine. Install dial indicator with point positioned on camshaft gear retaining bolt. Zero dial indicator.
2. Place large screwdriver between camshaft gear and block. Pull camshaft forward and then release. Replace thrust plate if dial indicator reading is not within limits.

Scheme 39

1. Remove rocker arm cover, rocker arm bolt, fulcrum seat and rocker arm. Ensure push rod end is in valve lifter socket. Install remote starter switch. Use dial indicator to check lobe lift in consecutive order.
2. Position dial indicator and cup-shaped adapter on end of push rod (in same plane as push rod movement). (Scheme 39) (Scheme 39): Checking Camshaft Lobe Lift Ensure push rod is in valve lifter socket.
3. Rotate crankshaft until lifter and push rod are at lowest position. Zero dial indicator. Rotate crankshaft slowly until push rod is in fully raised position. Record dial indicator reading and compare with specifications.
4. Maximum allowable lift loss is.005" (.127 mm). If lift on any lobe is below specifications, replace camshaft and valve lifters.

1. Remove engine from vehicle and remove flywheel. Remove camshaft and rear cam bearing plug. Remove crankshaft.
2. Push pistons to top of cylinders. Using Camshaft Bearing Remover/Installer (T65L-6250-A), drive out camshaft bearings.

1. Using bearing installer, install new bearings. Ensure oil holes in bearings align with oil holes in cylinder block.
2. Install front bearing so distance of .020-.035" (.51-.64 mm) exists between front edge of bearing and face of cylinder block.

OIL PAN

See OIL PAN REMOVAL article in the ENGINE section.

1. Remove cylinder head, oil pan and oil pump. Turn crankshaft until piston to be removed is at bottom of stroke. Place cloth over piston to collect metal cuttings.
2. Using ridge reamer, remove ridge and deposits from upper end of cylinder bore. Never cut into ring travel area in excess of 1/32" when removing ridge. Ensure all connecting rod caps are marked for cylinder identification. Remove connecting rod cap.
3. Using wooden hammer handle, push connecting rod and piston out top of cylinder. Avoid damage to crankshaft journal or cylinder wall, when removing piston and rod.

1. Properly install piston rings. (Scheme 40) Oil piston, rings and cylinder wall with light engine oil. Install ring compressor on piston, ensuring ring location does not change.
2. Place rod journal at bottom of its stroke. Place piston into cylinder bore, with notch on top of piston toward front of engine. Tap piston into cylinder bore, using wooden hammer handle.
3. Carefully guide rod over crankshaft journal, until it seats on journal. Install and tighten rod cap. Check rod side play.

FITTING PISTONS

Note. Take measurements with components at room temperature, about 70°F (21°C).

1. Measure piston at centerline of piston pin, 90° to piston pin axis. Measure cylinder bore 90° to crankshaft centerline, at top, middle and bottom of bore. Use these measurements to determine piston-to-cylinder bore clearance.
2. Measure cylinder bore 90° to crankshaft centerline at top of bore (below ring travel) and at bottom of bore (above ring travel). Taper is difference between 2 measurements, and must not exceed .010" (.25 mm).
3. Measure cylinder bore at center of piston travel, 90° to crankshaft centerline. Measure bore at center of piston travel, in line with crankshaft centerline. Out-of-round is difference between 2 measurements, and must not exceed .005" (.13 mm).
4. If taper or out-of-round are not within limits, or cylinder walls are deeply scored, hone or bore cylinders for installation of new pistons. See «PISTON SIZE CODE»(/ford/cab-chassis-ranger/1985-1986/remont/mechanical/#49l-6-cyl-vin-y) table.
5. If bore diameter is in lower third of range, Red piston should be used. In middle third of range, Blue piston should be used. For upper third of range, Yellow or .003" (stamped on dome) piston should be used.

PISTON SIZE CODE

FITTING RINGS

1. Position ring in cylinder bore at point where normal ring wear is not present. Exercise care not to damage ring or cylinder bore. Ring must be square in bore. Check ring end gap with feeler gauge.
2. Check side clearance of compression rings, with feeler gauge inserted between ring and its lower land. Feeler gauge should slide freely around entire circumference of piston without binding.
3. Properly install rings on piston. Space end gaps of oil ring segments 1" (25.4 mm) on either side of oil ring spacer end gap. (Scheme 40)

Correctly Spaced Piston Rings Space oil ring segments 1" (25.4 mm) from oil ring spacer. Scheme 40

Use press and Pin Remover/Installer (T68P-6135-A) to remove piston pin from piston and connecting rod.

Scheme 41

1. Lightly coat parts to be assembled with engine oil. Position piston and connecting rod as shown. (Scheme 41) (Scheme 41): Positioning Piston to Connecting Rod Press in piston pin until centered in connecting rod.
2. When properly assembled, notch on piston head will face toward front of engine, and bearing tang side of connecting rod will be positioned toward camshaft (left) side of engine.
3. Start piston pin in piston and connecting rod. Using press and Pin Remover/Installer (T68P-6135-A), push piston pin through piston until pin is centered in connecting rod. Ensure piston floats freely throughout press operation.

CONNECTING ROD BEARINGS

Note. Use Plastigage method for checking bearing clearances. Perform following procedures with oil pan and oil pump removed. Remove oil film from surfaces to be checked.

1. Ensure rod caps are marked for cylinder identification. Place crankshaft journal of cylinder to be checked at bottom of its stroke. Remove rod cap.
2. Clean crankshaft and bearings. Measure clearance using Plastigage method. Standard bearing may be used in combination with .001" (.025 mm) or .002" (.051 mm) undersize bearing to obtain proper bearing clearance. Try to obtain minimum specified clearance.
3. Install upper bearing in rod and pull rod down until bearing seats fully on journal. Install other bearing in rod cap. Install cap and tighten. Check rod side clearance.

MAIN BEARINGS

1. Fit main bearings individually, leaving other bearings securely fastened. Ensure main bearing caps are marked for identification.
2. Remove main bearing cap. Support crankshaft weight by placing jack under counterweight adjacent to bearing being checked.
3. Use Plastigage method to measure bearing clearance. Standard size bearings may be used in combination with .001" (.025 mm) or .002" (.051 mm) undersize bearing.
4. If .002" (.051 mm) undersize main bearings are used on more than one journal, install them on cylinder block side of crankshaft. NOTE: To replace rear main bearing, engine must be removed from vehicle.
5. Replace each main bearing set individually. Loosen all main bearing caps until they are finger tight. This will make it easier to remove and install upper bearings. Remove bearing cap to which new bearings are to be installed.
6. Insert Upper Bearing Remover/Installer (6331-E) into crankshaft journal oil hole. Turn crankshaft in direction of normal rotation to push upper bearing out of block. NOTE: Upper and lower bearing halves are not interchangeable. Upper half is drilled and grooved to provide entry of oil.
7. Lightly oil bearing and journal surfaces. Partially install plain end of upper bearing in place. Insert Upper Bearing Remover/Installer (6331-E) into journal oil hole.
8. Turn crankshaft slowly in opposite direction of normal rotation until bearing is seated. Remove bearing remover/installer. Install and tighten main bearing cap.

THRUST BEARING ALIGNMENT

1. Install thrust bearing cap after all other main caps have been tightened. Install thrust bearing cap bolts finger tight.
2. Pry crankshaft forward against thrust surface of upper half of bearing. Hold crankshaft forward and pry thrust bearing cap to rear. Tighten cap bolts, while holding forward pressure on crankshaft. (Scheme 42)

Aligning Thrust Bearing Align thrust bearing after tightening all other main bearing caps. Scheme 42

REAR MAIN BEARING OIL SEAL

Note. Seal may be replaced without removing crankshaft from engine.

1. Remove starter and transmission. Remove pressure plate and clutch disc (if equipped). Remove flywheel and engine rear cover plate. Using an awl, punch hole in oil seal metal surface between lip and block.
2. Screw threaded slide hammer end into hole and remove seal. Use care not to damage crankshaft oil seal surface. Clean oil seal recess in block and main bearing cap.

1. Inspect and clean crankshaft surface. Lightly coat crankshaft and new oil seal with engine oil. Start seal in place with lip facing forward. Use Seal Installer (T65P-6701-A) to drive in seal.
2. Keep installer straight in respect to centerline of crankshaft. Seal is properly installed when installer contacts cylinder block. Coat threads of flywheel bolts with oil resisting sealer. Reverse removal procedure to complete installation.

ENGINE OILING SYSTEM

Oil supply from pan is forced through lubrication system by rotor oil pump. Oil flows through full-flow oil filter, which routes oil into main oil gallery.

Oil gallery supplies oil to all internal engine bearings and lifters. Oil from lifters is forced through push rods to lubricate upper valve train area. Timing gears and chain are lubricated by splash method. (Scheme 43)

Engine Oiling System. Scheme 43

Crankcase Capacity

Crankcase capacity is 5 quarts (4.75L). Add 1 quart (.95L) when replacing oil filter.

Oil Filter

Full-flow filter has an integral by-pass valve. Anti-drain back feature prevents reverse flow of oil when engine is shut down. Replace filter at first oil change, then every second oil change thereafter.

Normal Oil Pressure

Normal oil pressure is 40-60 psi (2.8-4.2 kg/cm 2 ) at 2000 RPM.

Oil Pressure Regulator Valve

Oil pressure regulator valve is located in pump body. Valve is nonadjustable.

OIL PUMP

Note. Pump cannot be repaired. Replace complete pump assembly if any part requires replacement.

Remove oil pan. Remove nut securing oil pump inlet tube bracket to engine, and remove oil pump attaching bolts. Remove oil pump assembly.

Disassembly

1. Remove oil inlet tube. Remove cover attaching bolts and cover. Remove inner rotor and shaft and outer rotor.
2. Drill small hole into oil pressure relief valve cap. Insert self-threading sheet metal screw into cap, and pull cap from chamber. Remove spring and plunger. (Scheme 44)

Oil Pump Assembly Oil pump cannot be repaired. Scheme 44

1. Wash all parts thoroughly and dry with compressed air. Check inside of pump housing, outer rotor, inner rotor and shaft for damage, scoring or excessive wear. Check mating surface of pump cover for wear, scoring or grooved condition.
2. Remove rotor assembly from pump housing and place on flat surface. Using feeler gauge inserted to 1/2" minimum depth, measure inner to outer rotor tip clearance. Install rotor assembly in pump housing. Lay straightedge over rotor assembly and housing. Insert feeler gauge between straightedge and housing to measure rotor end play.
3. Measure outer rotor-to-housing clearance using feeler gauge. Measure shaft outside diameter and housing bearing inside diameter. Difference between readings is shaft-to-housing bearing clearance.
4. Relief valve spring should test to 20.6-22.6 lbs. (9-10 kg) at 2.49" (63.2 mm). Inspect relief valve spring for worn or collapsed condition.
5. Check relief valve plunger for scoring. Ensure plunger moves freely in bore. Check clearance between relief valve plunger and bore.

OIL PUMP SPECIFICATIONS

Reassembly

Clean and oil parts thoroughly. Install relief valve plunger, spring and new cap. Stake cap into position. Reassemble remaining components in reverse order of disassembly, using new gasket for oil inlet tube.

Prime oil pump by filling inlet opening with oil and rotating pump shaft until oil emerges from outlet opening. Install and tighten oil pump to cylinder block.

1. Drain cooling system. Remove alternator drive belt. On A/C equipped vehicles, remove air compressor drive belt.
2. Remove fan, spacer and pulley. Disconnect heater hose, lower radiator hose, and radiator supply line at water pump. Remove water pump.

1. Clean all gasket mating surfaces. Transfer fittings to new pump. Coat new gasket on both sides with gasket sealer and position gasket on water pump.
2. Install water pump and tighten attaching bolts. Reverse removal procedure to install remaining components.

Note. For further information on cooling systems, see ENGINE COOLING SYSTEM article in the ENGINE section.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

GENERAL ENGINE SPECIFICATIONS

GENERAL SPECIFICATIONS

VALVE SPECIFICATIONS

VALVE SPECIFICATIONS

PISTON/PIN/RING SPECIFICATIONS

PISTONS, PINS & RINGS SPECIFICATIONS

BEARING SPECIFICATIONS

CRANKSHAFT MAIN & CONNECTING ROD BEARINGS SPECIFICATIONS

VALVE SPRING SPECIFICATIONS

VALVE SPRINGS SPECIFICATIONS

CAMSHAFT SPECIFICATIONS

CAMSHAFT SPECIFICATIONS

See also:
• ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION
• VALVE CLEARANCE ADJUSTMENT