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

Exhaust Manifold Cleaning and Inspection

1. Inspect the cylinder head joining flanges of the exhaust manifold for evidence of exhaust gas leaks.
2. Inspect the exhaust manifold for cracks, damaged gasket surfaces, or other damage that would make it unfit for further use.

Scheme 1

1. Using a Micrometer measure the piston in two directions. Measure the piston diameter at the height of the piston pin bore, but offset by 90 degrees.

Scheme 2

1. Carry out a visual inspection. Clean the piston skirt, pin bush, ring grooves and crown and check for wear or cracks. If there are signs of wear on the piston skirt, check whether the connecting rod is twisted or bent.

Scheme 3

1. Measure the piston pin diameter. Measure the diameter in two directions. If the values are not to specification, install a new piston and a new piston pin.

Scheme 4

1. Measure the diameter of the piston pin bore. Measure the diameter in two directions. If the values are not to specification, install both a new piston and a new piston pin.

Scheme 5

1. Using the Feeler Gauge, measure the piston ring gap. The values given in the specification refer to a gauge ring used during production.

Inspection and Verification

Since diagnosis and testing actually begins when repairs are taken on, the following procedure is recommended.

1. Verify the customer concern by operating the system.
2. Visually inspect for obvious signs of mechanical damage or electrical damage. If the concern cannot be reproduced, carry out a road test and/or visual check with the aid of the following table. VISUAL INSPECTION Mechanical Coolant leaks Oil leaks Leaks in the fuel system Visibly damaged or worn parts Loose or missing nuts or bolts
3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
4. If the concern is not visually evident, verify the symptom and refer to the «SYMPTOM CHART»(ref-199536-S06292363962005101900000) .

Oil Consumption Test

The following diagnostic procedure is used to determine the source of excessive oil consumption.

Note. Oil use is normally greater during the first 16,100 km (10,000 miles) of service. As mileage increases, oil use decreases. Vehicles in normal service should get a least 16,000 km (10,000 miles) per liter. High speed driving, towing, high ambient temperature and other factors may result in greater oil use.

1. Define excessive consumption, such as the number of miles driven per liter of oil used. Also determine customers's driving habits, such as sustained high speed operation, towing, extended idle and other considerations.
2. Verify that the engine has no external oil leaks as described under «ENGINE OIL LEAKS»(ref-199536-S24653267592005101900000) .
3. Verify that the engine has the correct oil level.
4. Verify that the engine is not being run in an overfilled condition. Check the oil level at least five minutes after a hot shutdown with the vehicle parked on a level surface. In no case should the level be above the top of the cross-hatched area and the letter "F" in FULL. If significantly overfilled, carry out step 5, sub steps 1 . through 4.
5. Carry out an oil consumption test: Drain engine oil and fill with one liter less than the recommended amount. Run the engine for three minutes (10 minutes if cold), and allow oil to drain back for at least five minutes with vehicle parked on level surface. Remove the oil level indicator and wipe clean. (Do not wipe with anything contaminated with silicone compounds.) Install the oil level indicator making sure to seat the oil level indicator firmly in the oil level indicator tube. Remove the oil level indicator and draw a mark on the back (unmarked) surface at the indicated oil level. (This level should be about the same as the ADD mark on the face of the oil level indicator.) Add one liter of oil. Start the engine and allow to idle for at least two minutes. Shut off the engine and allow the engine oil to drain back for at least five minutes. Mark the oil level dipstick, using the procedure above. (This level may range from slightly below the top of the cross-hatched area to slightly below the letter "F" in FULL. Record the vehicles mileage. Instruct the customer to drive the vehicle as usual and: Check the oil level regularly at intervals of 160-240 km (100-150 miles). Check the oil level regularly at intervals of 160-240 km (100-150 miles). Check the oil level regularly at intervals of 160-240 km (100-150 miles). Return to the service point when the oil level drops below the lower (ADD) mark on the oil level indicator. Return to the service point when the oil level drops below the lower (ADD) mark on the oil level indicator. Return to the service point when the oil level drops below the lower (ADD) mark on the oil level indicator. Add only full liters of the same oil in an emergency. Note the mileage at which the oil is added. Add only full liters of the same oil in an emergency. Note the mileage at which the oil is added. Add only full liters of the same oil in an emergency. Note the mileage at which the oil is added. Check the oil level under the same conditions and at the same location as in steps 3 and 4 . Measure the distance from the oil level to the UPPER mark on the oil level indicator and record. Measure the distance from the oil level to the UPPER mark on the oil level indicator and record. Measure the distance from the oil level to the UPPER mark on the oil level indicator and record. Measure the distance between the two scribe marks and record. Measure the distance between the two scribe marks and record. Measure the distance between the two scribe marks and record. Divide the first measurement by the second. Divide the first measurement by the second. Divide the first measurement by the second. Divide the distance driven during the oil test by the result. This quantity is the approximate oil consumption rate in kilometers per liter or in mile per quart. Divide the distance driven during the oil test by the result. This quantity is the approximate oil consumption rate in kilometers per liter or in mile per quart. Divide the distance driven during the oil test by the result. This quantity is the approximate oil consumption rate in kilometers per liter or in mile per quart. If the oil consumption rate is unacceptable go to Step 6. If the oil consumption rate is unacceptable go to Step 6. If the oil consumption rate is unacceptable go to Step 6.
6. Check the positive crankcase ventilation (PCV) system. Make sure the system is not plugged.
7. Check for plugged oil drain-back holes in the cylinder head and cylinder block.
8. If the condition still exists after carrying out the above tests go to step 9.
9. Carry out a cylinder compression test. Refer to «COMPRESSION TEST»(ref-199536-S35751306832005101900000) . This can help determine the source of oil consumption such as valves, piston rings or other areas.
10. Check valve guides for excessive guide clearance. Install new valve stem seals after verifying valve guide clearance.
11. Worn or damaged internal engine components can cause excessive oil consumption. Small deposits of oil on the tips of the spark plugs can be a clue to internal oil consumption.

Intake Manifold Vacuum Test

Bring the engine to normal operating temperature. Connect a vacuum gauge or equivalent to the intake manifold. Run the engine at the specified idle speed.

The vacuum gauge should read between 51-74 kPa (15-22 in-Hg) depending upon the engine condition and the altitude at which the test is performed. Subtract 4.0193 kPa (1 in-Hg) from the specified reading for every 304.8 m (1,000 feet) of elevation above sea level.

The reading should be steady. As necessary, adjust the gauge damper control (where used) if the needle is fluttering rapidly. Adjust damper until needle moves easily without excessive flutter.