11
TROUBLE LOCATING CHART-contd.
Trouble
Reason
Causes
Suggested Remedy
Knocking
Carbon on piston crown
Injector needle sticking
Fuel timing too far advanced
Broken piston ring
Slack piston
Worn large end bearing
Loose flywheel
Worn main bearing
Decarbonise
Fit new nozzle
Adjust timing
Fit new ring
Fit new piston rings
Renew and check lubrication
Refit
Renew and check lubrication
Overheating
Cooling system failure:
Suction pipe blocked
Air leak in suction pipe
Broken water pump rotor
Faulty water pump seal
Overloaded
Excessive valve clearance Lubricating
oil failure
Check for leaks or blockages
Remove and clean
Check and tighten fittings
Replace rotor and check pump
Replace seal and check pump
Reduce the load Adjust
Check the engine and lubricating oil system for damage
If in order, top up sump and check running
Speed swrg—
Overheating
Air in fuel pipes
Governor slicking
See above
Bleed the system, if applicable
Check the governor for correct operation
Sudden stop
Empty fuel tank
Choked injector
Fuel pipe broken
Seized piston
Fill tank and bleed system, if applicable
Fit new nozzle
Repair or renew
Fit new cylinder and piston
Faulty running
Heavy vibration
Faulty installation
Check holding down bolts and flexible mountings and
couplings if fined