Engine System-General Information: Other Jaguar S-type I

Cylinder Head and Valve Train 3.0L

CYLINDER HEAD AND VALVE TRAIN 3.0L

Cylinder Head and Valve Train 4.0L

CYLINDER HEAD AND VALVE TRAIN 4.0L

Scheme 6

1. Inspect bearings for the following defects. Cratering - fatigue failure Spot polishing - incorrect seating. Imbedded dirt engine oil. Scratching - dirty engine oil. Base exposed - poor lubrication. Both edges worn-journal damaged. One edge worn - journal tapered or bearing not seated.

Scheme 7

Scheme 8

1. Position on a length of plastigage on the bearing cap. Insert the camshaft, without lubrication, into the cylinder head. Position a plastigage strip, which should be equal to the width of the bearing cap, on the bearing journal.
2. Install the camshaft bearing caps. Follow the relevant tightening sequence.
3. Remove the camshaft bearing caps. Follow the relevant loosening sequence.
4. Using the special tool, read off the measurement. Compare the width of plastigage with the plastigage scale. The value that is read off is the bearing clearance. If the values are not to specification install a new camshaft.

Scheme 9

1. Determine the diameter of the camshaft journals. Using a micrometer measure the diameter at 90 degrees intervals to determine if the journals are out-of-round. Measure at two different points on the journal to determine if there is any tapering. If the measurements are out of the specified range, install a new camshaft.

Scheme 10

1. Using the special tool, measure the end play. Slide the camshaft in both directions. Read and note the maximum and minimum values on the dial indicator gauge. End play = maximum value minus minimum value. If the measurement is out of specification, install new components.

Scheme 11

1. Measure the diameter (1) and diameter (2) with a vernier caliper. The difference in measurements is the lobe lift.

Scheme 12

1. Inspect camshaft lobes for pitting or damage in the active area. Minor pitting is acceptable outside the active area.

Connecting Rod Cleaning

1. Mark and separate the parts and clean with solvent. Clean the oil passages.

Scheme 13

Scheme 14

1. Measure the bearing bore in two directions. The difference is the connecting rod bore out-of-round. Verify the out-of-round is within specification.
2. Measure the bearing bore diameter in two directions. Verify the bearing bore is within specification.

Scheme 15

1. Using the Dial Indicator Gauge with Brackets, measure the end play. Measure the end play by lifting the crankshaft using a lever. If the value is out of the specification, install new thrust half rings to take up the end float and repeat the measurement.

Scheme 16

Scheme 17

1. Position on a length of Plastigage on the bearing journal. Insert the associated bearing shells, without lubrication, into the cylinder block. Insert the crankshaft, without lubrication, into the cylinder block. Position a strip of Plastigage, equal to the width of the bearing, on the bearing journal.
2. Carry out the measurement. Install the lower crankcase with bearing shells following the relevant tightening sequence.
3. Remove the lower crankcase with bearing shells.
4. Read off the measurement. Compare the length of plastigage with the Plastigage scale. The value that is read off is the bearing clearance. If the measurement is out of the specified range, change the bearing shells and repeat the measurement.

Scheme 18

1. Measure the cylinder bore with an internal micrometer. Carry out the measurements in different directions and at different heights to determine if there is any out-of-roundness or tapering. If the measurement is out of the specified range, hone out the cylinder block or install a new block.

Scheme 19

1. Measure the cylinder block/cylinder head distortion. Using the special tool, measure the mating face distortion. If the value is not to specification rework the mating face.

Piston Ring-to-Groove Clearance

1. Using the Feeler Gauge, measure the piston ring clearance.

Scheme 20

Scheme 21

1. Subtract the piston diameter from the cylinder bore diameter to find the piston to cylinder bore clearance.
2. Refer to corresponding illustration.

Scheme 22

1. Using a vernier gauge, measure the free length of each valve spring. Verify the length is within specification.

Scheme 23

1. Using a micrometer measure the diameter of the valve stems. If the measurements are not to specification, install a new valve.

3.0L Engine

The 3.0L engine consists of

1. A six cylinder 60 degree 'V' configuration liquid cooled aluminum cylinder block with dry steel liners.
2. Aluminum pistons with cut-outs in the piston crown to clear the valve heads for any available combination of camshaft profile and valve phasing.
3. Two aluminum cylinder heads with square squish chambers.
4. Two steel overhead camshafts per bank.
5. Four valves per cylinder.
6. Mechanical tappets and top mounted phosphate coated cast iron shims.
7. Variable valve timing (VVT) of the inlet camshafts.
8. Two silent timing chains with one hydraulic tensioner per chain.
9. Plastic camshaft covers with rubber seals.
10. A variable intake system containing two electrically controlled intake manifold tuning valves.
11. Plastic lower intake manifold with integral fuel rail and injectors.
12. Aluminum timing cover which accommodates the crankshaft front oil seal.
13. An oil pump mounted around the crankshaft.
14. An aluminum bed plate.
15. An aluminum oil pan.
16. A steel crankshaft.
17. Fracture-split connecting rods in sintered-forged steel.
18. A single, seven ribbed "V" belt drives the front end accessories.
19. An advanced engine management system incorporating electronic throttle control.
20. The unit meets the requirements of the CARB OBDII USA legislation.

The engine code and serial number is located on the front cover.

4.0L Engine

The 4.0L engine consists of

1. An eight cylinder 90 degree 'V' configuration liquid cooled aluminum cylinder block incorporating 'Nikasil' plated cylinder bores.
2. Pistons of open-ended skirt design, with two compression and one oil control ring. The piston crown has four cut-outs to clear the valve heads for any available combination of camshaft profile and valve phasing.
3. Two aluminum cylinder heads, each incorporating two camshafts.
4. Four valves per cylinder.
5. Aluminum tappets and top mounted shims.
6. Variable valve timing (VVT) of the inlet camshafts.
7. Camshaft covers manufactured from Vinylester.
8. Air assisted fuel injectors.
9. Aluminum timing cover which accommodates the crankshaft front oil seal.
10. Single row primary and secondary chains drive the camshafts of each cylinder bank.
11. An aluminum bed plate, incorporating iron main bearing supports, which accommodate the oil pump pick-up, diverter valve (if equipped) and oil filter.
12. Main bearings which are grooved in the upper positions and plain in the lower positions. They are manufactured from aluminum/tin material.
13. A crankshaft with undercuts and rolled fillets for extra strength.
14. Fracture-split connecting rods in sintered-forged steel.
15. Brackets bolted to the front of the cylinder block are used to mount all accessories.
16. A single, seven ribbed "V" belt drives the front end accessories.
17. An advanced engine management system incorporating electronic throttle control.
18. The unit meets the requirements of the CARB OBDII USA legislation.

The engine number is stamped onto the engine block adjacent to the thermostat housing.

Difficult to start during hot or cold start

Possible Source(s)

1. Piston ring(s) worn, damaged, sticking or worn piston/cylinder. Action(s) to take: INSTALL a new engine.

Possible Source(s)

1. Head gasket damaged. Action(s) to take: INSPECT the head gasket.

Possible Source(s)

1. Fuel system damaged or inoperative. Action(s) to take: Refer to «FUEL CHARGING & CONTROLS - 3.0L»(ref-199537) or «FUEL CHARGING & CONTROLS - 4.0L»(ref-199538)

Possible Source(s)

1. Ignition system inoperative. Action(s) to take: Refer to «ENGINE IGNITION - 3.0L»(ref-199539) or «ENGINE IGNITION - 4.0L»(ref-199540)

Poor Idling

Possible Source(s)

1. Restricted exhaust system. Action(s) to take: INSPECT the exhaust system.

Possible Source(s)

1. Vacuum leak. Action(s) to take: CARRY out the «INTAKE MANIFOLD VACUUM TEST»(ref-199536-S26763807152005101900000) . REPAIR and INSTALL new components as necessary.

Possible Source(s)

1. Burned valve(s). Action(s) to take: INSPECT the valve(s).

Possible Source(s)

1. Incorrect valve to valve seat contact. Action(s) to take: INSPECT the valve and valve seat.

Possible Source(s)

1. Head gasket damaged. Action(s) to take: INSPECT the head gasket.

Possible Source(s)

1. Fuel system damaged or inoperative. Action(s) to take: Refer to «FUEL CHARGING & CONTROLS - 3.0L»(ref-199537) or «FUEL CHARGING & CONTROLS - 4.0L»(ref-199538)

Insufficient power

Possible Source(s)

1. Compression leakage from valve seat. Action(s) to take: INSPECT the valve or valve seat.

Possible Source(s)

1. Valve sticking. Action(s) to take: INSPECT valve stem to valve guide clearance or carbon accumulation. Possible Source(s): Valve spring weak or broken. Action(s) to take: INSPECT the valve spring.

Possible Source(s)

1. Head gasket damaged. Action(s) to take: INSPECT the head gasket.

Possible Source(s)

1. Cylinder head cracked or distorted. Action(s) to take: INSPECT the cylinder head.

Possible Source(s)

1. Piston ring(s) worn, damaged or sticking. Action(s) to take: INSTALL a new engine.

Possible Source(s)

1. Fuel system damaged or inoperative. Action(s) to take: Refer to «FUEL CHARGING & CONTROLS - 3.0L»(ref-199537) or «FUEL CHARGING & CONTROLS - 4.0L»(ref-199538)

Possible Source(s)

1. Brakes dragging. Action(s) to take: Refer to «BRAKE SYSTEM-GENERAL INFORMATION»(ref-199527) .

Possible Source(s)

1. Restricted exhaust system. Action(s) to take: INSPECT the exhaust system.

Excessive or insufficient compression.

Possible Source(s)

1. Valve(s) burnt or sticking. Action(s) to take: INSPECT the valve(s).

Possible Source(s)

1. Valve spring(s) weak or broken. Action(s) to take: INSPECT the valve spring(s).

Possible Source(s)

1. Piston ring(s) worn, damaged, sticking or worn piston/cylinder. Action(s) to take: INSTALL a new engine.

Possible Source(s)

1. Head gasket damaged. Action(s) to take: INSPECT the head gasket.

Possible Source(s)

1. Carbon accumulation in combustion chamber. Action(s) to take: ELIMINATE carbon build up.

Possible Source(s)

1. Fuel system damaged or inoperative. Action(s) to take: Refer to «FUEL CHARGING & CONTROLS - 3.0L»(ref-199537) or «FUEL CHARGING & CONTROLS - 4.0L»(ref-199538)

Excessive oil consumption

Possible Source(s)

1. Piston ring(s) worn, damaged, sticking or worn piston/cylinder. Action(s) to take: INSTALL a new engine.

Possible Source(s)

1. Valve stem seal worn or missing. Action(s) to take: INSPECT the valve or valve stem seal.

Possible Source(s)

1. Oil leakage. Action(s) to take: REPAIR oil leakage.

Possible Source(s)

1. Valve stem or valve guide worn. Action(s) to take: INSPECT the valve stem or valve guide.

Possible Source(s)

1. Incorrect oil viscosity. Action(s) to take: DRAIN and FILL with new oil.

Possible Source(s)

1. Diluted oil. Action(s) to take: CHECK oil dilution. DRAIN and FILL as necessary.

Possible Source(s)

1. Crankcase overfilled. Action(s) to take: CHECK and adjust the oil level.

Possible Source(s)

1. Incorrect oil pressure. Action(s) to take: CHECK the oil pressure. REPAIR as necessary.

Engine Oil Leaks

Note. Before installing new gaskets or oil seals, make sure that the fault is clearly established.

If the oil leak cannot be identified clearly by a visual inspection, carry out an UV test

Fluorescent Oil Additive Method

1. Clean the engine with a suitable cleaning fluid (brake cleaner).
2. Drain the engine oil and refill with recommended oil, premixed with Diesel Engine Oil Dye or equivalent. Use a minimum 14.8 ml (0.5 ounce) to a maximum 29.6 ml (1 ounce) of fluorescent additive to all engines. If oil is not premixed, fluorescent additive must first be added to the crankcase.
3. Run engine for 15 minutes. Stop the engine and inspect all seal and gasket areas for leaks using a 12 Volt Master UV Diagnostic Inspection Kit or equivalent. A clear bright yellow or orange area will identify leak. For extremely small leaks, several hours may be required for the leak to appear.
4. As necessary, pressurize the main oil gallery system to locate leaks due to incorrectly sealed, loose or cocked plugs. If the flywheel bolts leak oil, look for sealer on the threads.
5. Repair all leaks as necessary.

General Remarks

Note. Removing fuses and disconnecting electrical components causes the powertrain control module (PCM) to log an error message. After the measurements have been carried out this error message should be cleared from memory by connecting to the Jaguar Approved Diagnostic System.

Note. Only check the compression pressure with the valves set to the prescribed clearance (if this can be adjusted).

The compression pressure should be checked with the engine at operating temperature.

Check The Compression Pressure

1. Remove the fuel pump relay.
2. Start the engine - the engine will start, run for a few seconds then stall.
3. Remove the spark plugs.
4. Install the compression tester.
5. Install an auxiliary starter switch in the starting circuit. With the ignition switch OFF, using the auxiliary starter switch, crank the engine a minimum of five compression strokes and record the highest reading. Note the approximate number of compression strokes required to obtain the highest reading.
6. Repeat the test on each cylinder, cranking the engine approximately the same number of compression strokes.
7. Install the components in reverse order, observing the specified tightening torques.
8. Reset the PCM fault memory.

Interpretation of the Results

The indicated compression pressure are considered within specification if the lowest reading cylinder is within 75% of the highest reading.

If the measurement on one or more cylinders is much lower than the specified value, spray some engine oil into the combustion chamber and repeat the compression measurement.

If the reading greatly improves then the piston rings are damaged.

If the reading stays the same then the cause is either damaged valve seats or valve stem seals.

If the measurements for two cylinders next to each other are both too low then it is very likely that the cylinder head gasket between them is burnt through. This can also be recognized by traces of engine oil in the coolant and/or coolant in the engine oil.

Excessive Engine Oil Consumption

The amount of oil an engine uses will vary with the way the vehicle is driven in addition to normal engine-to-engine variation. This is especially true during the first 16,100 km (10,000 miles) when a new engine is being broken in or until certain internal components become conditioned. Vehicles used in heavy-duty operation may use more oil. The following are examples of heavy-duty operation

1. Trailer towing applications.
2. Severe loading applications.
3. Sustained high speed operation.

Engines need oil to lubricate the following internal components

1. Cylinder block cylinder walls.
2. Pistons and piston rings.
3. Intake and exhaust valve stems.
4. Intake and exhaust valve guides.
5. All internal engine components.

When the pistons move downward, a thin film of oil is left on the cylinder walls. As the vehicle is operated, some oil is also drawn into the combustion chambers past the intake and exhaust valve stem seals and burned.

The following is a partial list of conditions that can affect oil consumption rates

1. Engine size.
2. Operator driving habits.
3. Ambient temperatures.
4. Quality and viscosity of oil.

Operation under varying conditions can frequently be misleading. A vehicle that has been run for several thousand miles on short trips or in below-freezing ambient temperatures may have consumed a "normal" amount of oil. However, when checking the engine oil level, it may measure up to the full mark on the oil level indicator due to dilution (condensation and fuel) in the engine crankcase. The vehicle then might be driven at high speeds on the highway where the condensation and fuel boil off. The next time the engine oil is checked it may appear that a liter of oil was used in about 160 km (100 miles) per liter oil consumption rate is about 2,400 km (1,500 miles) per liter.

Make sure the selected engine oil meets Jaguar specification and the recommended API performance category "SG" and SAE viscosity grade as shown in the vehicle Owner's Guide. It is also important that the engine oil is changed at the intervals specified for the typical operating conditions.

Interpreting Vacuum Gauge Readings

A careful study of the vacuum gauge reading while the engine is idling will help pinpoint trouble areas. Always conduct other appropriate tests before arriving at a final diagnostic decision. Vacuum gauge readings, although helpful, must be interpreted carefully.

Most vacuum gauges have a normal band indicated on the gauge face.

The following are potential gauge readings. Some are normal; others should be investigated further.

Scheme 24

1. NORMAL READING: Needle between 51-74 kPa (15-22 in-Hg) and holding steady.
2. NORMAL READING DURING RAPID ACCELERATION: When the engine is rapidly accelerated (dotted needle), the needle will drop to a low (not to zero) reading. When the throttle is suddenly released, the needle will snap back up to a higher than normal figure.
3. NORMAL FOR HIGH-LIFT CAMSHAFT WITH LARGE OVERLAP: The needle will register as low as 51 kPa (15 in-Hg) but will be relatively steady. Some oscillation is normal.
4. WORN RINGS OR DILUTED OIL: When the engine is accelerated (dotted needle), the needle drops to 0 kPa (0 in-Hg). Upon deceleration, the needle runs slightly above 74 kPa (22 in-Hg).
5. STICKING VALVES: When the needle (dotted) remains steady at a normal vacuum but occasionally flicks (sharp, fast movement) down and back about 13 kPa (4 in-Hg), one or more valves may be sticking.
6. BURNED OR BENT VALVES: A regular, evenly-spaced, downscale flicking of the needle indicates one or more burned or damaged valves. Insufficient hydraulic valve tappet or hydraulic lash adjuster clearance will also cause this reaction.
7. POOR VALVE SEATING: A small but regular downscale flicking can mean one or more valves are not seating correctly.
8. WORN VALVE GUIDES: When the needle oscillates over about a 13 kPa (4 in-Hg) range at idle speed, the valve guides could be worn. As engine speed increases, the needle will become steady if guides are responsible.
9. WEAK VALVE SPRINGS: When the needle oscillation becomes more violent as engine RPM is increased, weak valve springs are indicated. The reading at idle could be relatively steady.
10. LATE VALVE TIMING: A steady but low reading could be caused by late valve timing.
11. IGNITION TIMING RETARDING: Retarded ignition timing will produce a steady but somewhat low reading.
12. INSUFFICIENT SPARK PLUG GAP: When spark plugs are gapped too close, a regular, small pulsation of the needle can occur.
13. INTAKE LEAK: A low, steady reading can be caused by an intake manifold or throttle body gasket leak.
14. BLOWN HEAD GASKET: A regular drop of fair magnitude can be caused by a blown head gasket or warped cylinder head to cylinder block surface.
15. RESTRICTED EXHAUST SYSTEM: When the engine is first started and is idled, the reading may be normal, but as the engine RPM is increased, the backpressure caused by a clogged muffler, kinked tail pipe or other concerns will cause the needle to slowly drop to 0 kPa (0 in-Hg). The needle then may slowly rise. Excessive exhaust clogging will cause the needle to drop to a low point even if the engine is only idling. When vacuum leaks are indicated, search out and correct the cause. Excess air leaking into the system will upset the fuel mixture and cause concerns such as rough idle, missing on acceleration or burned valves. If the leak exists in an accessory such as the power brake booster, the unit will not function correctly. Always repair vacuum leaks.