New Holland CR9090 Tier 4a, Service Manual

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Engine - Engine and crankcase
Problem
Possible Cause Correction
The injection pump is delayed too much
or the automatic advance variator is dam-
aged. Correctly time the injection pump on the en-
gine or check the automatic advance vari-
ator.
The injection pump is delayed too much. Correctly time the injection pump on the en-
gine.
Partially and/or totally clogged or incor-
rectly set injectors. Clean, overhaul and adjust the injectors
correctly; change them if necessary.
Air cleaner clogged. Clean the unit and, if necessary, change
the filtering element.
Loss of compression in the engine caused
by:
- piston rings stuck;
- cylinder liners worn;
- valves worn or not adjusted. Change the damaged parts or, if necessary,
overhaul the engine.
Injection lines damaged. Check the conditions of the lines and
change them if necessary.
Blue, grey-blue or whitish
grey smoke. The injection pump is delayed too much
or the automatic advance variator is dam-
aged. Correctly time the injection pump on the en-
gine or check the automatic advance vari-
ator.
Blocked or faulty injectors. Clean, overhaul and set the injectors cor-
rectly, change them if necessary.
Oil passing from the piston rings caused by
stuck rings or liner wear. Change the damaged parts or, if necessary,
overhaul the engine.
Oil passing through the intake valve guide
caused by worn guides or valve stems. Overhaul the cylinder head.
The engine fails to reach operating temper-
ature (damaged thermostat). Change the thermostat.
Engine knocks Partially clogged or damaged injectors. Clean, overhaul and set the injectors cor-
rectly.
Collection of impurity in the fuel lines. Clean the lines and change heavily dam-
aged ones; if necessary, clean the injection
pump.
Incorrect timing of injection pump on en-
gine. Correctly time the injection pump on the en-
gine.
Crankshaft knocking caused by too much
clearance of one or more main or connect-
ing rod bearings or high shoulder clear-
ance. Grind the crankshaft pins, fit oversized
shoulder bearings and rings.
Crankshaft unbalanced. Check shaft alignment and balancing and
change it if necessary.
Slack flywheel fixing screws. Change the slackened screws and tighten
all screws to the specified angle.
Connection rods out of parallel. Straighten the connecting rods, check par-
allelism and, if necessary, change the ac-
tual connecting rods.
Pistons knocking due to abnormal wear. Bore the cylinder liners and fit oversized
pistons.
Noisy piston pins due to too much clear-
ance in the piston stubs and in the connect-
ing rod bushing. Bushings free in the hous-
ing on the connecting rod. Replace the piston pin with an oversized
one, reface the stubs on the piston and
the connecting rod bushings. Replace the
bushings with new ones.
Ticking due to noisy timing gear. Check for broken springs, too much clear-
ance between stems and guides, tappets
and seats; adjust the clearance between
valves and rockers.
Engine overheats Hose connection leaking or collapsed Tighten hose connection, renew hose if
damaged
Radiator cap defective or not sealing Renew radiator cap
Radiator leakage Repair/renew radiator
Improper fan belt adjustment Re-adjust fan belt
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