Loud tapping/knocking noise on cold start gq td42

[fireupson]

Hi all, i have done some research but cant seen to find the info i need.
I have gq lwb td42 turbo wiyh 316***kms, on cold start i have a knocking/tapping noise but then it goes away when warm. Serviced every 5000 penrite oil, ryco filters,I have no clue what it is.
Any help would be very much appreciated. thanks Tim

[luvpsi]

sounds like cold tappet clearances as when they warm up things expand and the clearances get better if not could just be the lifters

[boots]

With those sort of KM's also try some upper cylinder lube - home made brew - 2 stroke mineral oil mixed in to your diesel at 200 to 1 mix ratio . make sure its mineral based . definately makes a difference to engine noise at start up . see how it goes .

[nissannewby]

check your tappets bloke may just need a slight adjustment.

[fireupson]

thanks for your replys, i do use flash lube. How hard is it to adjust tappets?

[nissannewby]

Not to hard mate its quite easy get yourself a manual. Its gives you the correct order and measurement. You get no.1 on tdc do so many of the valves rotate engine 360 degrees and do the rest. Thats usually the quickest part depending on your turbo setup you may have to remove your airbox.

[mitchgq]

with tthat many k's chances are the the rockers will have a "dish" worn into them making adjusment near on impossible to get right because the feeler gauge wont contact the lowest worn point on the rocker. hope this makes sense.

[Diesel-Mate]

Valve clearances for sure, download the manual there easy to do.

[Kristofer go]

I too have the same problem with the noise. My motor has 350,000 km on it. The noise is strange as it comes and then goes away. I thought it might be water in the fuel or the fuel injectors need calibration. But I see where someone posted the valves could be the problem too. It is weird because I have added a bit of 5w 20 motor oil to the diesel and that has seemed to help. The noise is quite loud at times and I am afraid it could ruin the motor. Any more ideas or suggestions greatly appreciated!

[MudRunnerTD]

I did the tappets on the GUIV TD42Ti before i dyno'd it for the Madigan line and although the adjustment is Minute it may a fair difference to the noise of the engine. Mine has done 180k

I did not do it myself but went along and watch my bloke do it. Was a bit of stuffing around but pretty straight forward once you get the hang of it.

[Diesel-Mate]

You can go down to 13 thou on both intake and exhaust clearances, but you should really check If the rocker arms have worn grooves in them which will give you an inaccurate clearance reading. There about $30 each or you can get them refaced.