Komatsu D65EX-12 Operation & Maintenance Manual page 168

OPERATION
Problem
Abnormal noise generated
(combustion or mechanical)
Main causes
Low grade fuel being used
Overheating
Damage inside muffler
Excessive valve clearance
TROUBLESHOOTING
Remedy
Change to specified fuel
See item "Indicator of water tem-
perature gauge is in red range
on right side of gauge"
( Replace muffler)
( Adjust valve clearance)
3-121