LUBRICATING SYSTEM - L6
OIL PRESSURE RELIEF VALVE
The oil pressure relief valve is contained in a
housing bolted to the bottom face of the cylinder block
and is set to operate at 50/60 lbf/in2 (3,5/4.2 kgf/cm2) -
345/414 kN/m2.
To Remove and Dismantle the Relief Valve Assembly
1.
Remove the sump securing setscrews and
withdraw the sump from the engine.
2.
Disconnect the oil pump delivery pipe at the
relief valve end.
3.
Remove the one or two setscrews (according to
housing type) which secure the relief valve
housing to the cylinder block and take off the
relief valve housing.
4.
Remove the splitpin from the end of the relief
valve housing and withdraw the cap, spring and
plunger. An exploded view of the relief valve
assembly can be seen in Fig. L.11.
5.
Thoroughly clean all parts. Inspect them for
wear or damage and renew where necessary.
To Assemble and Refit the Relief Valve Assembly
1.
Fit the plunger, spring and cap to the relief valve
housing and secure with the split pin.
Fig. L.10.
Removing the Oil Relief Valve Housing from the
Cylinder Block.
Fig. L.11.
Exploded view of Oil Relief Valve.
1. Relief Valve Body.
2. Plunger.
3. Spring.
4. Spring Retaining Cap.
5. Splitpin.
2.
If a suitable test rig is available, check the
pressure setting of the relief valve. The valve
should lift between 50/60 lbf/in2 (3,5/4.2 kgf/
cm2). If a test rig is not available, extreme
caution is advised when starting the engine until
it has been ascertained that the pressure relief
valve is working correctly.
3.
Using a new joint (where fitted) fit the relief valve
housing to the cylinder block and secure with the
setscrew(s).
4.
Connect the oil pump delivery pipe to the relief
valve housing.
5.
Ensure that the sump strainer is correctly
positioned on the oil pump suction pipe. Using
new joints refit the sump to the engine and
secure with the retaining setscrews. Refill the
sump with clean oil of an approved grade.
OIL PRESSURE
Always ensure that with the engine running, oil
pressure is registering on the gauge or the oil pressure
warning light is extinguished.
Pressures do vary according to climatic conditions
and even between individual engines, but the oil
pressure range at maximum working speed is given on
Page B.8. The pressure will drop whilst the engine is
idling and also a slight drop will be experienced when
the oil is hot, this is quite normal. If, however, the oil
pressure is suspected of being too high or too low then
reference to the possible faults listed in Fault Diagnosis
may prove helpful.
