Im posting this just as a heads up to any members here. I just finished doing a headgasket on a 97 z24. it's fairly straight forward, with lots of bolts, nuts, and stuff to remove. the biggest problem for me, was the timing chain. When i first set it up, i had tension between the crank and intake, as well as tension between the cams. between the Water pump and ex. cam, was a little play, as well as between the water pump and crank.. I figured it wasn't terrible, and seeing as how everything was in line, i figured good to go. i attempted twice to roll the motor 720 degrees. each time, the chain would skip a tooth (specifically at the exhaust cam, but thats insignificant).

Here's the lesson. DONT BE LIKE ME (in this instance). I assumed that since the tensioner is driven off of oil pressure, surely it will work fine (without the chain skipping) once started. man. i was wrong. started it up, and it ran, but not good. not good at all. firing out the exhaust. i knew what happened. the chain jumped.

why? two issues at work here. 1.) the engine has 116xxx miles, and as such the chain develops a bit of stretch/wear. I don't know what the specification is, but when i compared the new to the old, i found a good difference. 2.) the tensioner was a bit sticky, and its oil pressure operated. so for a brief moment, there is not enough tension. thats all it takes, a brief moment.


luckily, all it cost me was $100 for a new chain, tensioner, and tensioner guide/shoe. and of course two more hours taking apart and re-assembling the timing stuff.

SUMMARY: When doing a headgasket, or anything that requires removal of timing components, REPLACE the tensioner, and at least inspect the chain.

Did you reset the tensioner correctly? I have no problem reusing the tensioner in either of my 2.4s. I say inspect the tensioner and replace the chain. Thats what I did when I did the HG in my 98 (did it for @!#$s and grins).