VDL Futura FHD2 E6, Руководство по ремонту

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Futura FHD2/FMD2 E6
DIAGNOSIS
3 - 9
Components
2
DD1020_01
PISTON
Valve impressions on the piston base
A number of pistons have a valve mark
Impressions on the piston base
The piston base is cracked
Pitting on the piston base
Possible cause Remedy
A broken valve spring. Check the valve springs.
Possible cause Remedy
The valve timing is incorrect. Check the valve timing.
A distribution gear wheel is loose. Check the distribution gear wheels.
The engine runs at a speed which is too high when all the
outlet valves have touched the pistons. Check the gearbox’s safety device.
Check the engine protection data in the engine manage-
ment system.
Instruct the driver if the engine has had a too high engine
speed a number of times.
One or more teeth on the camshaft gear wheel are in the
wrong position. Check the position of the camshaft gear wheel.
Possible cause Remedy
During work, a foreign object has got into the combustion
chamber via the inlet/exhaust manifold. Check the other pistons, the cylinder lining and the
valves for damage.
Check the inlet and outlet systems.
Possible cause Remedy
The mixture is too rich. Check the engine management system.
The wrong injection moment. Check the engine management system.
Poor fuel distribution due to poorly operating injectors. Check the operation of the injectors.
Fuel injection when the engine brake is applied. Check the engine management system.
The piston base has touched the cylinder head; there are no cracks.
Possible cause Remedy
The wrong cylinder head gasket has been fitted. Check whether the correct cylinder head gasket has
been fitted.
Excessive play on the piston rod bearing or the piston pin
is worn. Check the piston rod and the piston.