VDL Futura FHD2 E6, Workshop Manual

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Futura FHD2/FMD2 E6
DIAGNOSIS
Components
3 - 8
2
DD1020_01
The bearing shells are excessively worn
The bearing shell has grooves on it
Possible cause Remedy
The lubrication oil has been diluted by coolant. Check the oil cooler.
Check the cylinder block and the cylinder heads for
cracks or a knocked head gasket by pressure-testing the
cooling system.
Check the bearing necks for damage and see whether
they are the correct size.
Check and clean the lubricating oil system.
The lubrication oil has been diluted by fuel. Check the fuel system.
Check the bearing necks for damage and see whether
they are the correct size.
Check and clean the lubricating oil system.
Contaminated lubricating oil due to:
- Contaminated oil filter.
- Not changing the oil soon enough.
- Not replacing the oil filter soon enough.
- Excessive contamination within the replacement
period.
- Worn areas on the rotating section.
- Broken oil filter.
- Dirt which was not removed after assembly. Check the bearing necks for damage and see whether
they are the correct size.
If the bearing necks have grooves, the crankshaft will
have to be replaced or ground.
Check and clean the lubricating oil system.
Too little lubricating oil due to:
- The oil level being poorly checked.
- Too low oil level.
- Not topping up the oil.
- Excessive oil use.
- An external oil leak.
- Air bubbles in the lubrication system due to a loose
oil delivery line.
The connecting rod bearings will be damaged first in the
event of reduced oil pressure, because they are further
away from the oil pump than the main bearing.
Check the engine for external oil leaks.
Check the bearing necks for damage and see whether
they are the correct size.
If the bearing necks have grooves, the crankshaft will
have to be replaced or ground.
Check and clean the lubricating oil system.
No lubricating oil due to:
- Loose or worn oil drain plug.
- Blocked oil duct.
- Incorrectly assembled bearing.
If there is a sudden loss of oil, the main bearings will
become worn first, because they will immediately not
receive any more oil.
Check the bearing necks for damage and see whether
they are the correct size.
If the bearing necks have grooves, the crankshaft will
have to be replaced or ground.
Check and clean the lubricating oil system.
Possible cause Remedy
Dirt has got between the bearing shell and the initial bore
of the main bearing or the piston rod during assembly. Replace the bearing shells.
Check the bearing necks for damage and see whether
they are the correct size.
Check and clean the lubricating oil system.