hello dieseldude,

well ung prob kasi ng 123 ko is may noise coming from the engine na wasnt really there before. sabi ng friend ko na may 123 din it may be fuel knock kasi kaka overhaul lang kasi nung march ng 123 ko and sabi nya it may need calibration na para mawala ung noise. what do u think dieseldude? thanks..will be waiting for ur reply.

First thing to do is the check injection pump to engine timing, most especially of knock comes from all cylinders.

Faulty nozzle/s can also cause fuel knock. Loosen one high pressure line at a time. If Knock stops on a specific cylinder, then you may have a possible faulty injector. Interchange injectors between a good cylinder and a knocking cyinder. If knock transfers, problem is on that specific injector.

Sometimes, fuel knock comes from unequal comrpession pressures between cylinders on newly ovehauled engines. But since your engine is now almost 1 year since overhaul, we can assume that cylinder compression is normal if overhaul and break-in were properly done.

Knock can also be due to unequal timing and fuel output from each pumping element of the injection pump.

Try the first two tests first: timing and injector analysis before proceeding to the more expensive tests.

I suggest that we transfer to our Diesel Fuel Injection Helpdesk at the worshop forum.