Forum:
I recently cooked the engine in my 1999 2.8 fourtrak, it's been rebuilt by myself, now its going it seems noisy and i'm at a loss as to why, the only thing i didn't replace were the small end bearings but the noise seems to be top end, i'm using a 10/40 semi synthetic oil, i hve been told some engines don't like certain oils but i think i'm grasping at straws !!! Any suggestions will be gratefully recieved. Thanks, KWD
Top end noise
Hi KWD,
Start with the obvious, have to checked the valve clearences again since the rebuild?
Top end noises can be from the valve train(pushrods, rockers or valves), either from excessive clearence or lack of oil to the rocker shaft. While checking the valves make sure you have oil coming from all of the rockers arms. I have known people to fit the head gasket upside down and block off the oil feed up to the head. I don't know if this can happen with the Fourtrak head gasket.
Another cause of top end noise is a diesel knock due to a faulty injector or injection pump. If you can't find a problem with the valves then try running the engine and go along the injector pipes slackening them off about half a turn one at a time to see if you can hear the knock disappear. If the nosie goes and you can isolate the cylinder that it is knocking on then you could try swapping that injector with another to see if the knock follows the injector or stays with the cylinder
Daz
Its Getting Better
Daz,
Yes mate re-set the clearences and re-checked them several times, set them at what it says on the rocker cover today, 0.25 inlet, 0.35 exhaust, changed the oil and filter, checked the injectors, and the rocker shaft and it is allot better. It doesn't seem so bad when you initially start up, gets a bit worse as it warms up (not as bad as it was). Only thing i'm going to check is the oil pressure, was going to put a guage in where the oil pressure switch fits but i'm open to any other suggestions. In the re-built it has basically had everything done, pistons, rings, gudgeon pins, big end shells, cam, followers, head skimmed, valved re-ground and seated. The only thing i can think i didn't change was the little ends but i measured them up.
Cheers, KWD
nois
Did you change the oil pump if you fit new big ends you should always put new oil pump on as the bearings are much tighter
WE AL MAKE MISTAKES SAID THE DARLEK GETTING OFF THE DUSTBIN
WE AL MAKE MISTAKES SAID THE DARLEK GETTING OFF THE DUSTBIN
Noise
No I didn't, I imagine that will have to be my next job then. Thanks for the information.