Engine System-General Information: Other Ford Taurus IV рестайлинг

Material

MATERIAL SPECIFICATION

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 all sealing surface areas with a suitable solvent to remove all traces of oil.

Engine Oil Leaks-Fluorescent Oil Additive Method

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

1. Add gasoline engine oil dye. 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 crankcase.
2. Run the engine for 15 minutes. Stop the engine and inspect all seal and gasket areas for leaks using the UV Leak Detector Kit. A clear bright yellow or orange area will identify the leak. For extremely small leaks, several hours may be required for the leak to appear.

Leakage Points-Underhood

Examine the following areas for oil leakage

1. valve cover gaskets
2. intake manifold gaskets
3. cylinder head gaskets
4. oil bypass filter
5. oil filter adapter
6. engine front cover
7. oil filter adapter and filter body
8. oil level indicator tube connection
9. oil pressure sensor

Leakage Points-Under Engine-With Vehicle on Hoist

1. oil pan gaskets
2. oil pan sealer
3. oil pan rear seal
4. engine front cover gasket
5. crankshaft front seal
6. crankshaft rear oil seal
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 installed)
5. camshaft rear bearing covers 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.

Compression Pressure Limit Chart

COMPRESSION PRESSURE LIMIT CHART

If one or more cylinders reads low, squirt approximately one tablespoon of engine oil on top of the pistons in the low-reading cylinders. Repeat the compression pressure check on these cylinders.

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 will be heard in the throttle body. A leak at the exhaust valve can be heard at the tail pipe. 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.

Excessive Engine Oil Consumption

Nearly all engines consume oil, which is essential for normal lubrication of the cylinder bore walls and pistons and rings. Determining the level of oil consumption may require testing by recording how much oil is being added over a given set of miles.

Customer driving habits greatly influence oil consumption. Mileage accumulated during towing or heavy loading generates extra heat. Frequent short trips, stop-and-go type traffic or extensive idling, prevent the engine from reaching normal operating temperature. This prevents component clearances from reaching specified operating ranges.

The following diagnostic procedure may be utilized to determine internal oil consumption. Make sure that the concern is related to internal oil consumption, and not external leakage, which also consumes oil. Verify there are no leaks before carrying out the test. Once verified, the rate of internal oil consumption can be tested.

A new engine may require extra oil in the early stages of operation. Internal piston-to-bore clearances and sealing characteristics improve as the engine breaks in. Engines are designed for close tolerances and do not require break-in oils or additives. Use the oil specified in the Owner Guide. Ambient temperatures may determine the oil viscosity specification. Verify that the correct oil is being used for the vehicle in the geographic region in which it is driven.

Basic Pre-checks

1. For persistent complaints of oil consumption, interview the customer to determine the oil consumption characteristics. If possible, determine the brand and grade of oil currently in the oil pan. Look at the oil filter or oil-change station tags to determine if Ford-recommended maintenance schedules have been followed. Make sure that the oil has been changed at the specified mileage intervals. If vehicle mileage is past the first recommended drain interval, the OEM production filter should have been changed.
2. Ask how the most current mileage was accumulated. That is, determine whether the vehicle was driven under the following conditions: Extended idling or curbside engine operation Stop-and-go traffic or taxi operation Towing a trailer or vehicle loaded heavily Frequent short trips (engine not up to normal operating temperature) Excessive throttling or high engine-rpm driving
3. Verify that there are no external leaks. If necessary, review the diagnostic procedure under Engine Oil Leaks in «DIAGNOSIS AND TESTING»(ref-233705-S15480254442006052600000) .
4. Inspect the crankcase ventilation system for: disconnected hoses at the valve cover or throttle body. loose or missing valve cover fill cap. missing or incorrectly seated engine oil level indicator. incorrect or dirty PCV valve. a PCV valve grommet unseated in the valve cover (if so equipped)
5. Inspect for signs of sludge. Sludge affects PCV performance and can plug or restrict cylinder head drainback wells. It can also increase oil pressure by restricting passages and reducing the drainback capability of piston oil control rings. Sludge can result from either excessive water ingestion in the crankcase or operation at extremely high crankcase temperatures.
6. Inspect the air filter for dirt, sludge or damage. A hole in the filter element will allow unfiltered air to bypass into the air induction system. This can cause premature internal wear (engine dusting), allowing oil to escape past rings, pistons, valves and guides.
7. If the engine is hot or was recently shut down, wait at least five minutes to allow the oil to drain back. Ask the customer if this requirement has been followed. Adding oil without this wait period can cause an overfill condition, leading to excessive oil consumption and foaming which may cause engine damage.
8. Make sure the oil level indicator (dipstick) is correctly and fully seated in the indicator tube. Remove the oil level indicator and record the oil level.

Detailed Pre-checks

1. Check the thermostat opening temperature to make sure that the cooling system is operating at the specified temperature. If it is low, internal engine parts are not running at specified internal operating clearances.
2. Verify the spark plugs are not oil saturated. Oil leaking into one or more cylinders will appear as an oil soaked condition on the plug. If a plug is saturated, a compression check may be necessary at the conclusion of the oil consumption test.

Post Checks, Evaluation and Corrective Action

1. If test results indicate excessive oil consumption, carry out a cylinder compression test. The cylinder compression test should be carried out with a fully charged battery and all spark plugs removed. See the «COMPRESSION PRESSURE LIMIT CHART»(ref-233705-S17908035252006052600000) for pressure range limits.
2. Compression should be consistent across all cylinders. For additional information, refer to «COMPONENT TESTS»(ref-233705-S39900364762006052600000) . If compression tested within the specifications found in this section, the excessive oil consumption may be due to wear on the valve guides, valves or valve seals.
3. A cylinder leak detection test can be carried out using an Engine Cylinder Leak Detection/Air Pressurization Kit. This can help identify valves, piston rings or worn valve guides/valve stems, inoperative valve stem seals or other related areas as the source of oil consumption. NOTE: An oil-soaked appearance on the porcelain tips of the spark plugs also indicates excessive oil use. A typical engine with normal oil consumption will exhibit a light tan to brown appearance. See «SPARK PLUG INSPECTION»(ref-233705-S08725212042006052600000) for details. A single or adjoining, multiple cylinder leak can be traced by viewing the tips.
4. If an internal engine part is isolated as the root cause, determine if the repair will exceed cost limits and proceed with a repair strategy as required.
5. Once corrective action to engine is complete and verifying that all pre-check items were eliminated in the original diagnosis, repeat the Oil Consumption Test as described above and verify consumption results.

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, Rocker Arm

1. Check for loose mounting bolts, studs and nuts.
2. Check for plugged oil feed in the rocker arms or cylinder head.

Valve Train Analysis-Engine Off, Camshaft Roller Followers and Hydraulic Lash Adjusters, Overhead Camshaft

1. Check for loose mounting bolts on camshaft carriers.
2. Check for plugged oil feed in the camshaft roller followers, lash adjusters or cylinder heads.

Valve Train Analysis-Engine Off, Camshaft-Engines

1. Check for broken or damaged parts.

Valve Train Analysis-Engine Off, Push Rods

1. Check for bent push rods and restricted oil passage.

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 on the valve stem and in valve spring retainer.
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 guide-mounted valve stem seal.
4. Check collapsed valve tappet gap.
5. Check installed valve spring height.
6. Check for missing or worn valve spring seats.
7. 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 Running

1. Start the engine and, while idling, check for correct operation of all parts. Check the following

Valve Train Analysis-Engine Running, Valves and Cylinder Head

1. Check for plugged oil drain back holes.
2. Check for missing or damaged valve stem seals or guide mounted valve stem seals.
3. Check for a plugged oil metering orifice in the cylinder head oil reservoir (4.6L engine only).

If insufficient oiling is suspected, check oil passages for blockage, then accelerate the engine to 1,200 rpm with the transmission in NEUTRAL and the engine at normal operating temperature. Oil should spurt from the rocker arm oil holes such that valve tips and camshaft roller followers are well oiled. With the valve covers off, some oil splash may overshoot camshaft roller followers.

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

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

Scheme 730

1. Remove the valve covers.
2. Remove the spark plugs.
3. Install the Dial Indicator Gauge with Holding Fixture 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 (1) 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 (2) base circle is reached. The indicator reading should be zero. If zero reading is not obtained, repeat Steps 1 through 6.
7. Remove the Dial Indicator Gauge with Holding Fixture.
8. Install the spark plugs.
9. Install the valve covers.

Valve Train Analysis-Engine Running, Camshaft Lobe Lift-Push Rod Engine

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

1. Remove the valve covers.
2. Remove the rocker arm seat bolts, rocker arm seat and rocker arms.
3. Make sure the valve tappet is seated against camshaft. Install (1) Dial Indicator Gauge with Holding Fixture so the ball socket adapter of the indicator is on top of the valve tappet or (2) Dial Indicator Gauge Adapter is on top of push rod and in same plane as valve tappet push rod movement.
4. Remove the spark plugs.
5. Connect an auxiliary starter switch in the starting circuit. Crank the engine with ignition switch in OFF position. Bump crankshaft over until valve tappet is on base circle of camshaft lobe. At this point, valve tappet will be in its lowest position. If checking during engine assembly, turn crankshaft using a socket or ratchet.
6. Zero the dial indicator. Continue to rotate crankshaft slowly until valve tappet is in fully-raised position (highest indicator reading).
7. Remove the Dial Indicator with Holding Fixture, Dial Indicator Gauge Adapter, and auxiliary starter switch.
8. Install rocker arm seats, rocker arms and rocker arm seat bolts.
9. Install valve covers.
10. Install spark plugs.

Valve Train Analysis-Engine Running, Valve Tappet

Valve tappet noise can be caused by any of the following

1. excessive valve tappet gap (collapsed)
2. incorrectly functioning valve tappet
3. air in lubrication system
4. excessive valve guide wear
5. low oil pressure

Excessive collapsed valve tappet gap can be caused by loose rocker arm seat bolts/nuts, incorrect initial adjustment or wear of valve tappet face, or worn roller valve tappets, push rod, rocker arm, rocker arm seat or valve tip. With valve tappet collapsed, check gap between the valve tip and the rocker arm to determine if any other valve train parts are damaged, worn or out of adjustment.

An incorrectly functioning valve tappet can be sticking, caused by contaminants or varnish inside the tappet. The tappet can have a check valve that is not functioning correctly, which can be caused by an obstruction, such as dirt or chips that prevent the check valve from closing, or a broken check valve spring. A tappet with a leakdown time out of specification can cause tappet noise. If no other cause for noisy valve tappets can be found, the leakdown rate should be checked and new valve tappets installed if found to be out of specification.

Assembled valve tappets can be tested with Hydraulic Tappet Leakdown Tester to check the leakdown rate. The leakdown rate specification is the time in seconds for the plunger to move a specified distance while under a 22.7 kg (50 lb) load.

Air bubbles in the lubrication system will prevent the valve tappet from supporting the valve spring load. This can be caused by too high or too low an oil level in the oil pan or by air being drawn into the system through a hole, crack or leaking gasket on the oil pump screen cover and tube.

Sprockets

1. Inspect the timing chain/belt and the sprockets. Install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Rocker Arms - Cleaning

1. Clean all parts thoroughly. Make sure all oil passages are open.
2. Make sure oil passage in the push rod/valve tappet end of the rocker arm is open.

Push Rods - Cleaning

1. Clean the push rods in a suitable solvent. Blow out the oil passage in the push rods with compressed air.

Camshaft Journal - Clearance, Push Rod Engines, Micrometer Method

1. Measure each camshaft bearing in 2 directions. Subtract the camshaft journal diameter from the camshaft bearing diameter.

Camshaft Bearing Journal Clearance

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

1. Remove the camshaft bearing cap and lay Plastigage across the surface. Refer to the appropriate ENGINE MECHANICAL article for the procedure.
2. Position the camshaft bearing cap and install the bolts. Refer to the appropriate ENGINE MECHANICAL article for the procedure.
3. Use Plastigage to verify the camshaft journal clearance. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Crankshaft Main Bearing Journal-to-Bearing Clearance

Note. Crankshaft main bearing journals must be within specifications before checking journal clearance.

Scheme 731

Scheme 732

1. Remove the crankshaft main bearing caps and crankshaft main bearing.
2. Lay a piece of Plastigage across the face of each crankshaft main bearing surface.
3. Install and remove the crankshaft main bearing cap.
4. Verify the crankshaft journal clearance. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Connecting Rod Bearing Journal Taper and Out-of-Round

1. Measure the crankshaft connecting rod journal diameters in 2 directions perpendicular to one another at each end of the connecting rod journal. The difference in the measurements from one end to the other is the taper. Verify measurement is within the wear limit. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 733

1. Measure the cylinder bore at the top, middle and bottom of piston ring travel in 2 directions as indicated. Verify the cylinder bore is within the wear limit. The difference indicates the cylinder bore taper. Bore the cylinder to the next oversize limit. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 734

1. Measure the cylinder bore in 2 directions. The difference is the out-of-round. Verify the out-of-round is within the wear limit and bore the cylinder to the next oversize limit. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Piston Pin to Bore Diameter

1. Measure the piston pin bore diameter in 2 directions on each side. Verify the diameter is within specification. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 735

1. Measure the piston diameter 90 degrees from the piston pin and 42 mm (1.65 in) down from the top of the piston at the point indicated. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Piston To Cylinder Bore Clearance

1. Subtract the piston diameter from the cylinder bore diameter to find the piston-to-cylinder bore clearance.

Piston Selection

Note. The cylinder bore must be within the specifications for taper and out-of-round before fitting a piston.

1. Select a piston size based on the cylinder bore.
2. Choose the piston with the correct paint color. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Piston Ring End Gap

Note. Cylinder bore must be within specification for taper and out-of-round.

Scheme 736

Scheme 737

1. Use a piston without rings to push a piston ring in a cylinder to the bottom of ring travel.
2. Use a feeler gauge to measure the top piston ring end gap and the second piston ring end gap. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 738

Scheme 739

1. Inspect the piston for ring land damage or accelerated wear.
2. Measure the piston ring-to-groove clearance. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 740

1. Measure the piston pin diameter in 2 directions at the points shown. Verify the diameter is within specification. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Connecting Rod Cleaning

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

Scheme 741

1. Tighten the bolts to specification, then measure the bore in 2 directions. The difference is the connecting rod bore out-of-round. Verify the out-of-round is within specification. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 742

Scheme 743

1. Use a telescoping gauge to determine the inner diameter of the connecting rod bushing, if equipped.
2. Measure the telescoping gauge with a micrometers. Verify the diameter is within specification. Refer to the appropriate ENGINE MECHANICAL article for the specification. If out of specification, install new components as necessary.

Scheme 744

1. Measure the connecting rod bend on a suitable alignment fixture. Follow the instructions of the fixture manufacturer. Verify the bend measurement is within specification. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 745

1. Measure the connecting rod twist on a suitable alignment fixture. Follow the instructions of the fixture manufacturer. Verify the measurement is within specification. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 746

1. Measure the clearance between the connecting rod and the piston. Verify the measurement is within specification. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Connecting Rod Bearing Journal-to-Bearing Clearance

Note. The crankshaft connecting rod journals must be within specifications to check the connecting rod bearing journal clearance.

Scheme 747

Scheme 748

1. Remove the connecting rod bearing cap.
2. Position a piece of Plastigage across the bearing surface.
3. Install and tighten to specifications, then remove the connecting rod bearing cap.
4. Measure the Plastigage to get the connecting rod bearing journal clearance. The Plastigage should be smooth and flat. A changing width indicates a tapered or damaged connecting rod or connecting rod bearing. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 749

1. Measure the clearance between the connecting rod and the crankshaft. Verify the measurement is within specification. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 750

1. Inspect the roller for flat spots or scoring. If any damage is found, inspect the camshaft lobes and valve tappet for damage. Push rod engines

Valve and Seat Refacing Measurements

Scheme 751

1. Check the valve head and seat. Check valve angles. Check margin width. Refer to the appropriate ENGINE MECHANICAL article for the procedure. Be sure margin width is within specification.
2. Inspect for abnormalities on the valve face and seat.

Scheme 752

1. Measure the valve seat width. If necessary, grind the valve seat to specification. Measure the intake valve seat width. Measure the exhaust valve seat width. Recheck the valve spring installed length after the seats have been ground, and shim the valve springs as necessary to achieve the correct installed spring length. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 753

1. Use a valve seat runout gauge to check valve seat runout.

Cylinder Head Distortion

1. Using a straightedge and a feeler gauge, inspect the cylinder head for flatness in the sequence shown. If the cylinder head is distorted, install a new cylinder head.

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 clean engine oil meeting Ford specification.

MATERIAL SPECIFICATION

Scheme 754

1. Use a slide hammer or tools suitable to remove the cylinder block core plug.
2. Inspect the cylinder block plug bore for any damage that would interfere with the correct sealing of the plug. If the cylinder block plug bore is damaged, bore for the next oversize plug.
3. Coat the cylinder block core plug and bore lightly with Threadlock 262 and install the cylinder block core plug.

Cup-Type

1. Use a tool suitable to seat the cup-type cylinder block core plug.

Expansion-Type

1. Use tool suitable to seat the expansion-type cylinder block core plug.

Scheme 755

Scheme 756

Scheme 757

Scheme 758

Scheme 759

Scheme 760

Scheme 761

1. Inspect the spark plug for a bridged gap. Check for deposit build-up closing the gap between the electrodes. Deposits are caused by oil or carbon fouling. Clean the spark plug.
2. Check for oil fouling. Check for wet, black deposits on the insulator shell bore electrodes, caused by excessive oil entering the combustion chamber through worn rings and pistons, excessive valve-to-guide clearance or worn or loose bearings. Correct the oil leak concern. Install a new spark plug.
3. Inspect for carbon fouling. Look for black, dry, fluffy carbon deposits on the insulator tips, exposed shell surfaces and electrodes, caused by a spark plug with an incorrect heat range, dirty air cleaner, too rich a fuel mixture or excessive idling. Clean the spark plug.
4. Inspect for normal burning. Check for light tan or gray deposits on the firing tip.
5. Inspect for pre-ignition, identified by melted electrodes and a possibly damaged insulator. Metallic deposits on the insulator indicate engine damage. This may be caused by incorrect ignition timing, wrong type of fuel or the unauthorized installation of a heli-coil insert in place of the spark plug threads. Install a new spark plug.
6. Inspect for overheating, identified by white or light gray spots and with bluish-burnt appearance of electrodes. This is caused by engine overheating, wrong type of fuel, loose spark plugs, spark plugs with an incorrect heat range, low fuel pump pressure or incorrect ignition timing. Install a new spark plug.
7. Inspect for fused deposits, identified by melted or spotty deposits resembling bubbles or blisters. These are caused by sudden acceleration. Clean the spark plug.