1992 GQ Patrol Bad Diesel Knock.

Hey Hump

Firstly - what motor..... the 4.2 or 3.0?

Didn't touch anything south of the head gasket?

When you had the head off - did you have it shaved....or just whack it back on? Reason I ask is that normally heads are (hopefully) usually chemically cleaned to remove all carbon deposits in the combusion chambers (and everywhere else) - which if you still have plenty of, then this could cause dieseling and pre-ignition anywhere during the induction stroke.

Did you put the timing chain back on correctly and know that you don't have a timing issue?

Did you take out the injectors prior to pulling the head off? Or did you leave the injectors in the head whilst you worked on the broken stud?

Bilbo

When you say the correct gasket, there are 3 thickness gaskets on the TD42 if thats the engine you have...

When does the knock occur? When you start it, or all the time?
coming from front or back of engine?

Didnt leave something in there did you?

Check your valve clearances, sounds like a valve hitting a piston to me.

To Chrispy, the td42 dont have timing chains, and to remove the head you wouldnt remove the front gear train, the petrol tb42 had chains.

Did you check the valves after fitting the head, the pushrods will be slightly different lengths (very small) which will put the clearences out.
Could also be a bad injector which will knock when running.
Rev engine up and crack the injector lines to eliminate that problem, the knock will go if that is the problem.

I need an engine for a truck build up im doing, How much!!

Hey Hump where is your little Brother? You sure you didn't put him in that mighty 4.2 block and he's knocking like crazy to get out?