TROUBLESHOOTING
TESTING AND ADJUSTING
7. TOO MUCH VIBRATION
Cause
Correction
Loose Bolt or Nut Holding Pulley or
Tighten bolt or nut.
Damper
Pulley or Damper Has A Defect
Install a new pulley or damper.
Fan Blade Not in Balance
Loosen or remove fan belts and operate engine for a short time at the
rpm that the vibration was present. If vibration is not still present,
make a replacement of the fan assembly.
Engine Supports Are Loose, Worn,
Tighten all mounting bolts. Install new components if necessary.
or Have a Defect
Misfiring or Running Rough
Make Reference to Item 3.
8. LOUD COMBUSTION NOISE (KNOCK)
Cause
Correction
Bad Quality Fuel
Remove the fuel from the fuel tank. Install a new fuel filter element.
Put a good grade of clean fuel in the fuel tank.
Defect in Fuel Injection Valve(s) or
Run engine at rpm that gives maximum combustion noise. Then
Fuel Injection Pump(s)
loosen a fuel line nut on the injection pump for each cylinder, one at a
time. Find the cylinder where loosening the fuel line nut stops the
combustion noise. Test the injection pump and injection valve for
that cylinder. Install new parts where needed.
Wrong Fuel Injection Timing
Make adjustment to timing.
9. LOUD NOISE (CLICKING) FROM VALVE COMPARTMENT
Cause
Correction
Damage to Valve Spring(s) or Locks
Install new parts where necessary. Locks with defects can cause the
valve to slide into the cylinder. This will cause much damage.
Not Enough Lubrication
Check lubrication in valve compartment. There must be a strong flow
of oil at engine high rpm, but only a small flow of oil at low rpm. Oil
passages must be clean, especially those sending oil to the cylinder
head.
Too Much Valve Clearance
Make adjustment. See the Subject VALVE CLEARANCE in Test-
ing and Adjusting.
Damage to Valves
Make a replacement of the valve(s) and make an adjustment as
necessary.
