Engine System-General Information: Other Ford Thunderbird XI

Engine Oil Leaks

Note. When diagnosing engine oil leaks, the source and location of the leak must be positively identified prior to repair.

Prior to carrying out this procedure, clean the cylinder block, cylinder heads, valve covers, oil pan and flywheel with a suitable solvent such as Engine Degreaser (F4AZ-19A536-A) to remove all traces of oil. Make sure the oil in the crankcase is of the correct viscosity and the correct level.

Engine Oil Leaks-Fluorescent Oil Additive Method

Use the UV Leak Detector Kit to carry out the following procedure for oil leak diagnosis.

1. Clean the engine with a suitable solvent to remove all traces of oil.
2. Add Gasoline Engine Oil Dye 164-R3705 meeting Ford specification ESE-M99C103-B1 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 the oil is not premixed, fluorescent additive must first be added to the case.
3. Run the engine for 15 minutes. Stop the engine and inspect all seal and gasket areas for leaks using the 12 Volt Master UV Diagnostic Inspection Kit. A clear bright yellow or orange area will identify the leak. For extremely small leaks, several hours may be necessary for the leak to appear.

Leakage Points-Underhood

Examine the following areas for oil leakage

1. valve cover gaskets
2. cylinder head gaskets
3. oil cooler, if equipped
4. oil filter adapter
5. engine front cover
6. oil filter adapter and filter body
7. oil level indicator tube connection
8. oil pressure sensor

Leakage Points-Under Engine-With Vehicle on Hoist

1. oil pan gaskets (6710)
2. oil pan sealer
3. sump sealer - 8 cyl.
4. engine front cover gasket
5. crankshaft front seal (6700)
6. crankshaft rear oil seal (6701)
7. crankshaft main bearing cap side bolts
8. oil filter adapter and filter body
9. oil cooler, if equipped

Leakage Points-With Transmission and Flywheel Removed

1. crankshaft rear oil seal
2. rear main bearing cap parting line
3. rear main bearing cap and seals
4. flywheel mounting bolt holes (with flywheel (6375) installed)
5. camshaft rear bearing covers (6266) or pipe plugs at the end of oil passages

Oil leaks at crimped seams in sheet metal parts and cracks in cast or stamped parts can be detected when using the dye method.

Cylinder Leakage Detection

When a cylinder produces a low reading, use of the Engine Cylinder Leak Detection/Air Pressurization Kit will be helpful in pinpointing the exact cause.

The leakage detector is inserted in the spark plug hole, the piston is brought up to dead center on the compression stroke, and compressed air is admitted.

Once the combustion chamber is pressurized, a special gauge included in the kit will read the percentage of leakage. Leakage exceeding 20 percent is excessive.

While the air pressure is retained in the cylinder, listen for the hiss of escaping air. A leak at the intake valve (6507) will be heard in the throttle body (9E926). A leak at the exhaust valve (6505) can be heard at the tailpipe. Leakage past the piston rings will be audible at the positive crankcase ventilation (PCV) connection. If air is passing through a blown head gasket to an adjacent cylinder, the noise will be evident at the spark plug hole of the cylinder into which the air is leaking. Cracks in the cylinder block or gasket leakage into the cooling system may be detected by a stream of bubbles in the radiator (8005).

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 engine 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, pin and rings (6102)
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 duty cycle
2. operator driving habits
3. ambient temperature
4. quality and viscosity of the oil
5. oil filler cap not seated
6. oil level indicator not seated

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 or MAX on the oil level indicator due to dilution (condensation and fuel) in the engine crankcase. The vehicle might then 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 (quart) of oil was used in about 160 km (100 miles). This perceived 160 km (100 miles) per liter (quart) oil consumption rate causes customer concern even though the actual overall oil consumption rate is about 2400 km (1500 miles) per liter (quart).

Make sure the selected engine oil meets the current recommended API performance category with SAE viscosity grade as shown in the vehicle Owner Literature. It is also important that the engine oil is changed at the intervals specified. Refer to the Vehicle Owner Literature.

Valve Train Analysis-Engine Off-Valve Cover Removed

Check for damaged or severely worn parts and correct assembly. Make sure correct parts are used with the static engine analysis as follows.

Valve Train Analysis-Engine Off

1. Check for loose mounting bolts on camshaft caps.
2. Check valve shim to camshaft gap.

Valve Train Analysis-Engine Off, Camshaft-Engines

1. Check for broken or damaged parts.

Valve Train Analysis-Valve Springs

1. Check for broken or damaged parts.

Valve Train Analysis-Engine Off, Valve Spring Retainer and Valve Spring Retainer Keys

1. Check for correct seating of the valve spring retainer key (6518) on the valve stem and in valve spring retainer (6514).
2. Check for correct seating on the valve stem.

Valve Train Analysis-Engine Off, Valves and Cylinder Head

1. Check for plugged oil drain back holes.
2. Check for worn or damaged valve tips.
3. Check for missing or damaged valve stem seals or guide-mounted valve stem seal.
4. Check valve tappet shim gap.
5. Check for missing or worn valve spring seats.
6. Check for plugged oil metering orifice in cylinder head oil reservoir (if equipped).

Static checks (engine OFF) are to be made on the engine prior to the dynamic procedure.

Valve Train Analysis-Engine Off, Camshaft Lobe Lift-OHC Engines

Check the lift of each camshaft lobe in consecutive order and make a note of the readings.

Scheme 8

1. Remove the valve covers.
2. Remove the spark plugs.
3. Install the special tool so the rounded tip of indicator is on top of the camshaft lobe and on the same plane as the valve tappet.
4. Rotate the crankshaft using a breaker bar and socket attached to the crankshaft pulley retainer bolt. Rotate the crankshaft until the base circle of the camshaft lobe is reached.
5. Zero the dial indicator. Continue to rotate the crankshaft until the high-lift point of the camshaft lobe is in the fully-raised position (highest indicator reading).
6. To check the accuracy of the original indicator reading, continue to rotate crankshaft until the base circle is reached. The indicator reading should be zero. If zero reading is not obtained, repeat Steps 1 through 6.
7. Install the spark plugs.
8. Install the valve covers.

Valve Train Analysis-Engine Off, Valve Tappet

Valve tappet noise can be caused by any of the following

1. excessive valve tappet shim gap
2. excessive valve guide wear

Excessive collapsed valve tappet shim gap can be caused by loose rocker arm seat bolts/nuts, incorrect initial adjustment or wear of valve tappet shim face.

Refer to VALVE-Stem to Valve Guide Clearance .

Scheme 9

1. Inspect the timing chain/belt and the sprocket. Install new components as necessary. Refer to «TIMING DRIVE COMPONENTS -- PRIMARY»(ref-204559-S09416534882005111300000) and «TIMING DRIVE COMPONENTS -- SECONDARY»(ref-204559-S00879160002005111300000) for the procedure.

Scheme 10

1. Measure each camshaft journal diameter in two directions. If it is out of specification, install a new camshaft. Refer to «CAMSHAFT»(ref-204559-S13019775132005111300000) for the procedure.

Camshaft Journal

Note. The camshaft journals must meet specifications before checking camshaft journal clearance.

Refer to CAMSHAFT JOURNAL-Diameter for the procedure.

Camshaft-End Play, OHC Engines

Special Tool(s)

Scheme 11

Scheme 12

1. Use the special tool to measure camshaft end play.
2. Position the camshaft to the rear of the cylinder head.
3. Zero the indicator.
4. Move the camshaft to the front of the cylinder head. Note and record the camshaft end play. If camshaft end play exceeds specifications, install new camshaft thrust bearing washers.

Scheme 13

1. Inspect camshaft lobes for pitting or damage in the active area. Minor pitting is acceptable outside the active area. If excessive pitting or damage is present, install a new camshaft, refer to «CAMSHAFT»(ref-204559-S13019775132005111300000) for the procedure.

Camshaft-Lobe Lift

Special Tool(s)

Scheme 14

Scheme 15

1. Use the special tool to measure camshaft intake/exhaust lobe lift. Rotate the camshaft and subtract the lowest indicator reading from the highest indicator reading to figure the camshaft lobe lift. For additional information, refer to «GENERAL SPECIFICATIONS»(ref-204559-S13128603732005111300000) .

Camshaft-Runout

Special Tool(s)

Scheme 16

Scheme 17

1. Use the special tool to measure the camshaft runout. Rotate the camshaft and subtract the lowest indicator reading from the highest indicator reading. For additional information, refer to «GENERAL SPECIFICATIONS»(ref-204559-S13128603732005111300000) . . If it is out of specification, install a new camshaft. Refer to «CAMSHAFT»(ref-204559-S13019775132005111300000) for the procedure.

Scheme 18

1. Measure the diameter of each intake and exhaust valve stem at the points shown. Verify the diameter is within specification. Refer to «GENERAL SPECIFICATIONS»(ref-204559-S13128603732005111300000) . If out of specification, install new components as necessary. Refer to «ENGINE»(ref-204559) for the procedure.

Valve-Stem to Valve Guide Clearance

Special Tool(s)

Scheme 19

Note. Valve stem diameter must be within specifications before checking valve stem to valve guide clearance.

1. Using special tool Valve Stem Checking Tool and Dial Indicator with Bracketry, lower the valve until the Valve Stem Checking Tool contacts the upper surface of the valve guide.
2. Move the Valve Stem Checking Tool toward the indicator and zero the indicator. Move the Valve Stem Checking Tool away from the indicator and note the reading. The reading will be DOUBLE the valve stem-to-valve guide clearance.

Scheme 20

1. Inspect the following valve areas: the end of the stem for grooves or scoring the valve face and the edge for pits, grooves or scores the valve head for signs of burning, erosion, warpage and cracking the valve margin for wear

Scheme 21

1. Measure the inner diameter of the valve guides in two directions where indicated. Refer to «GENERAL SPECIFICATIONS»(ref-204559-S13128603732005111300000) . .

Scheme 22

1. Measure the free length of each valve spring. «GENERAL SPECIFICATIONS»(ref-204559-S13128603732005111300000) . If out of specification, install new components as necessary. Refer to «ENGINE»(ref-204559) for the procedure.

Scheme 23

1. Measure the out-of-square on each valve spring. Turn the valve spring and observe the space between the top of the valve spring and the square. Install a new valve spring if out of square. Refer to «VALVE SPRINGS»(ref-204559-S40184163682005111300000) for the procedure.

Valve-Spring Strength

Special Tool(s)

Scheme 24

Scheme 25

1. Use the special tool to check the valve spring for correct strength at the specified valve spring length. «GENERAL SPECIFICATIONS»(ref-204559-S13128603732005111300000) . If out of specification, install new components as necessary. Refer to «ENGINE»(ref-204559) for the procedure.

Valve and Seat Refacing Measurements

Scheme 26

1. Check the valve head and seat. Check valve angles. Check margin width. Refer to «GENERAL SPECIFICATIONS»(ref-204559-S13128603732005111300000) . . Be sure margin width is within specification.
2. Inspect for abnormalities on the valve face and seat.

Scheme 27

1. Measure the valve seat width. Install a new cylinder head if measurements are not within specification. Refer to «CYLINDER HEAD»(ref-204559-S23053388382005111300000) for the procedure. Measure the intake valve seat width. Measure the exhaust valve seat width. Refer to «GENERAL SPECIFICATIONS»(ref-204559-S13128603732005111300000) . .

Scheme 28

1. Check valve seat runout. Verify that the runout is within specification.

Cylinder Head-Distortion

Special Tool(s)

Scheme 29

Scheme 30

1. Use the special tools to inspect the cylinder head for flatness. If the cylinder head is distorted, install a new cylinder head. Refer to «CYLINDER HEAD»(ref-204559-S23053388382005111300000) for the procedure.

Cylinder Bore-Cleaning

1. Clean the cylinder bores with soap or detergent and water.
2. Thoroughly rinse with clean water and wipe dry with a clean, lint -free cloth.
3. Use a clean, lint-free cloth and lubricate the cylinder bores. Use engine oil meeting Ford specification.

Cylinder Block-Distortion

Special Tool(s)

Scheme 31

Scheme 32

1. Use the special tools to inspect the cylinder block for flatness. If the cylinder block is distorted, install a new cylinder block.