Yanmar YM276 Service Manual page 470

220-104 System Tests and Diagnosis
DIAGNOSING ENGINE MALFUNCTIONS [Continued)
PROBLEM POSSIBLE CAUSE SUGGESTED REMEDY
Low oil pressure
Basic Engine Problem
(Grow indicator light)
.
Faulty pressure regulating valve setting
Adjust valve
.
Excessive main and connecting r o d Replace bearings
clearance
Plugged oil pump intake screen Clean screen
Worn o i l pump Replace p u m p
Service Problem
L o w oil level
.
lmproper o i l viscosity
Operator Error
Engine speed t o o slow
A d d o i l
Replace w i t h correct viscosity oil
Place throttle lever t o correct position
High oil pressure
Basic Engine Problem
.
Stuck o r improperly adjusted Replace o r adjust valve
regulating valve
Black exhaust smoke
Fuel System Malfunction
.
Improper injection timing
Excessive injection rate
.
Faulty nozzle spray
Operator Error
.
Engine overloaded
Service Problem
Clogged air cleanel
White exhaust smoke
Basic Engine Problem
.
L o w compression
Operator Error
.
Engine N o t warmed up
Excessive fuel
Basic Engine Problem
consumption
L o w compression
Fuel System Malfunction
Improper injection p u m p timing
.
Excessive fuel delivery
Adjust timing
Adjust governor system
Clean nozzles
Reduce load
Clean air cleaner
Check valve clearance
Warmupengine
Check valve clearance, head gasket for
leaks and cylinder liner clearance
Adjust p u m p timing
Adjust governor system
SMEZ7601118304 YM276and
2760
Kznamoto. Prcnfed in Japan