WEICHAI WD10 Service Manual - page 153
Service Manual for WD10 Diesel Engine
143
Check and adjust bearing shell clearance.
(6) Air compressor leaking oil
Fault phenomenon: Lubricating oil oozes from air compressor housing.
Possible causes:
1) Oil seal has fallen off or oil seal is damaged.
2) Main shaft is loose.
3) Oil leakage in junction surface, oil inlet and return pipe joints are loose.
4) The belt is too tight, which results in wear of main bearing shell.
5) Casting or manufacturing deficiency
Troubleshooting:
1) Oil seal
Check whether oil seal is fractured, whether its inner lip is cracked or turnup, replace the seal if
any situation listed above occurred. Check the junction surface between oil seal and main shaft
for scratch and flaw, scratched and flawed parts should be replaced. Check whether return oil is
unblocked, blocked return oil will cause high oil pressure in crankcase that leading to oil
leakage in seal or oil seal falling off. Oil return pipe diameter must meet the minimum
requirements, and the pipe should not be twisted. Check the fit dimension of oil seal and
crankcase, replace the unfitted seal.
2) Move the main shaft with all your strength to check whether the radial clearance is too large,
replace the bearing shell and seal if so.
3) Check all sealing gaskets for sealing performance, repair or replace the gasket; check fixing
bolts of oil inlet pipe joint, oil return pipe joint and the housing, and tighten them.
4) Check and adjust the belt tightness degree (press the belt with your thumb, it is suitable if the
belt is depressed about 10mm).
5) Check compressor housing for casting or manufacturing deficiency (whether the oil return hole
is unblocked), repair or replaced the flawed housing.
(7) Air compressor overheating
Fault phenomenon: Air compressor exhaust temperature is too high; the running parts are hot.
Possible causes:
1) The relief valve or unloading valve isn’t working, which caused the compressor fail to take a
break.
2) Severe leakage in air brake system, which caused the compressor fail to take a break.
3) Insufficient oil supply to the running parts or scuffing.