New Holland 40 Series Repair Manual page 23

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PROBLEM
Engine knocks
POSSIBLE CAUSES
1. Diluted or thin oil
2. Insufficient oil supply
3. Low oil pressure
4. Excessive crankshaft end
play
5. Flywheel or ring gear
run-out excessive
6.
Excessive connecting rod
or main bearing clearance
7.
Bent or twisted connecting
rods
8. Crankshaft journals out-
of-round
9. Excessive piston-to-
cylinder bore clearance
10. Excessive piston ring
clearance
11. Broken rings
12. Excessive piston pin
clearance
13. Piston pin retainer loose or
missing
14. Excessive camshaft play
15. Imperfections on timing
gear teeth
16. Excessive timing gear
backlash
5
REMEDY
1 . Check crankshaft bearings
for damage, change as
required. Drain and refill
with specified oil and renew
filter. Ascertain cause of
dilution
2. Check oil level and top up
as necessary. Overhaul or
renew pump as necessary.
Check oil filter is not
clogged
3. Overhaul pump or relief
valve as necessary
4. Install new thrust bearing
liner
5. Skim flywheel or fit new ring
gear
6.
Install new bearing inserts
and/or re-grind crankshaft
7.
Renew connecting rods
8. Re-grind crankshaft and fit
undersize bearing inserts
9. Re-bore/re-sleeve block
and fit new pistons
10. Fit new pistons and rings
11. Fit new rings, check bore
and pistons for damage
12. Fit new piston or pin
13. Install new retainer and
check bore/pistons for
damage
14. Install new thrust plate
15. Renew timing gear
16. Renew timing gear