SDLG WP6, Service Manual

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Service Manual for WP6 Diesel Engine
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bearing shell is worn or damaged that result in crash noise.
2) The belt is too loose, driving and driven pulley groove type is not uniform, which lead to
slipping squeal.
3) No engine oil is supplied to air compressor, dry friction of metal leading to squeal.
4) Loose fixing bolts.
5) Loose gear fastening nuts results in oversized tooth space, which will bring rhythmic knock.
6) Foreign matter in piston head.
Troubleshooting:
1) Check whether connecting rod bearing shells, connecting rod sleeve and main bearing shell is
worn or damaged, whether connecting rod bolts are loose; check whether air compressor main
oil gallery is unblocked; replace the severely worn or damaged bearing shells, sleeve and main
bearing shell; tighten connecting rod bolts to 35Nm~40Nm; unblock the main oil gallery with
compressed air.
2) Check whether the driving and driven pulley groove type is uniform, replace if not. Adjust the
belt tightness degree (press the belt with your thumb, it is suitable if the belt is depressed about
10mm).
3) Check engine oil pressure (air compressor oil inlet port), check whether engine oil pipe is
damaged or blocked, adjust, clean or replace the invalid pipe if the oil pressure is insufficient;
Check engine oil quality and impurity content, compare it with application standard, replace the
oil immediately if out of limits; check whether there is engine oil supplied to air compressor,
conduct a comprehensive inspection if not.
4) Check whether compressor fixing bolts are loose and tighten them.
5) For gear-driven compressor, check the fitting condition of the gears, tighten loose nuts, and
replace the gear if there is fitting problem.
6) Clean up foreign matter.
(5) Air compressor “burning”
Fault phenomenon: For belt-driven compressor, its main shaft is locked; for gear-driven
compressor, the bearing shell or connecting rod bearing shell is abnormally loose.
Possible causes:
1) The lubricating oil is deteriorated or too many impurities in the oil.
2) Insufficient oil supply or no oil supply.
3) Compressor inner oil channel is blocked by misplaced bearing shell.
4) Damaged bearing shell or connecting rod bearing shell, or too small fit clearance.