Engine System-General Information: Other Ford Econoline E250

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.

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

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
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

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 dipstick 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 2,400 km (1,500 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's Guide. It is also important that the engine oil is changed at the intervals specified.

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, 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 - 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 installed valve spring height.
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 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.

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

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

Scheme 23

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.

Scheme 24

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

Scheme 25

1. Measure each camshaft journal diameter in two directions. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Camshaft Journal - Clearance, Plastigage Method

SPECIAL TOOL(S)

Scheme 26

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 procedure.
2. Position the camshaft bearing cap and install the bolts. Refer to the appropriate ENGINE MECHANICAL article
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.

Camshaft End Play

SPECIAL TOOL(S)

Scheme 27

Scheme 28

1. Use a Dial Indicator Gauge with Holding Fixture 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 and recheck end play. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If camshaft end play exceeds specification after camshaft installation, install a new cylinder head. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 29

1. Inspect camshaft lobes for pitting or damage in the contact area. Minor pitting is acceptable outside the contact area. If excessive pitting or damage is present, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Camshaft Lobe Lift

SPECIAL TOOL(S)

Scheme 30

Scheme 31

1. Use a Dial Indicator Gauge with Holding Fixture 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. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Camshaft Runout

SPECIAL TOOL(S)

Scheme 32

1. Use a Dial Indicator Gauge with Holding Fixture to measure the camshaft runout. Rotate the camshaft and subtract the lowest indicator reading from the highest indicator reading. For additional information, refer to the specification chart in the appropriate ENGINE MECHANICAL article. If out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 33

1. Measure each of the crankshaft main bearing journal diameters in at least two directions. 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 34

1. Measure each of the crankshaft main bearing journal diameters in at least two directions at each end of the main bearing journal. 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.

Crankshaft Main Bearing Journal - Clearance

SPECIAL TOOL(S)

Scheme 35

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

Scheme 36

Scheme 37

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.

Crankshaft End Play

SPECIAL TOOL(S)

Scheme 38

Scheme 39

1. Measure the crankshaft end play. Use a Dial Indicator Gauge with Holding Fixture to measure crankshaft end play.
2. Position the crankshaft to the rear of the cylinder block.
3. Zero the indicator.
4. Move the crankshaft to the front of the cylinder block. Note and record the crankshaft end play. If crankshaft end play exceeds specifications, install a new crankshaft thrust washer (6334) or crankshaft thrust main bearing (6337). Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Crankshaft Runout

SPECIAL TOOL(S)

Scheme 40

1. Use the Dial Indicator Gauge with Holding Fixture to measure the crankshaft runout. Refer to the appropriate ENGINE MECHANICAL article for the procedure. Rotate the crankshaft and subtract the lowest dial indicator reading from the highest dial indicator reading to figure the crankshaft runout. If it is out of specification, install new components as necessary. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 41

1. Measure the crankshaft connecting rod journal diameters in two 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 42

1. Measure the cylinder bore at the top, middle, and bottom of piston ring travel in two 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. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 43

1. Measure the cylinder bore in two 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 - 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.

Scheme 44

1. Select a piston size based on the cylinder bore.
2. Choose the piston with the correct paint color or specific size grade. 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 45

Scheme 46

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 47

Scheme 48

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 49

1. Measure the piston pin diameter in two 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 50

1. Tighten the bolts to specification, then measure the bore in two 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 51

1. Measure the inner diameter of the connecting rod bushing, if equipped. 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.

Scheme 52

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 53

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 54

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.

Connecting Rod - Bearing Journal Clearance

Special Tool(s)

Scheme 55

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

Scheme 56

Scheme 57

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 58

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.

Scheme 59

Scheme 60

1. Inspect the roller follower for flat spots or scoring. If any damage is found, inspect the camshaft lobes and hydraulic lash adjuster for damage.

Scheme 61

1. Inspect the hydraulic lash adjuster and roller follower for damage. If any damage is found, inspect the camshaft lobes and valves for damage.

Scheme 62

1. Measure the diameter of each intake and exhaust valve stem 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.

Valve Stem to Valve Guide Clearance

SPECIAL TOOL(S)

Scheme 63

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

1. Install a Valve Guide Clearance Gauge on the valve stem and install a Dial Indicator Gauge with Holding Fixture. Lower the valve until the Valve Guide Clearance Gauge contacts the upper surface of the valve guide.
2. Move the Valve Guide Clearance Gauge toward the indicator and zero the indicator. Move the Valve Guide Clearance Gauge away from the indicator and note the reading. The reading will be DOUBLE the valve stem-to-valve guide clearance. Valves with oversize stems will need to be installed if out of specification.

Scheme 64

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 65

1. Measure the inner diameter of the valve guides in two directions where indicated. Refer to the appropriate ENGINE MECHANICAL article for the procedure.
2. If the valve guide is not within specifications, ream the valve guide and install a valve with an oversize stem or remove the valve guide and install a new valve guide.

Scheme 66

1. Use a hand-reaming kit to ream the valve guide.
2. Reface the valve seat.
3. Clean the sharp edges left by reaming.

Scheme 67

1. Measure the installed length of each valve spring. Refer to the appropriate ENGINE MECHANICAL article for the procedure. If out of specification, install new components. Refer to the appropriate ENGINE MECHANICAL article for the procedure.

Scheme 68

1. Measure the free length of each valve spring. 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 69

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 the appropriate ENGINE MECHANICAL article.

Valve Spring Strength

SPECIAL TOOL(S)

Scheme 70

Scheme 71

1. Use a Valve/Clutch Spring Pressure Gauge to check the valve spring for correct strength at the specified valve spring length. 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.

Valve and Seat Refacing Measurements

Scheme 72

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 73

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 74

1. Use the 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.