aluminum block?

99 gt 100k


Hello everyone,
I have another problem, I blew the head gaskets on my car and it is now hydro locked.:banghead: I plan on changing the gaskets his weekend, but need to know if its worth it. Is the L36 an iron or aluminum block? how about the heads? And with it being hydro-locked is there a good chance i burnt a piston or maybe cracked a sleeve? Does anyone know or know where to get the torque specs for this kinda job? thank you for your help!!

99 gt 100k


Hello everyone,
I have another problem, I blew the head gaskets on my car and it is now hydro locked.:banghead: I plan on changing the gaskets his weekend, but need to know if its worth it. Is the L36 an iron or aluminum block? how about the heads? And with it being hydro-locked is there a good chance i burnt a piston or maybe cracked a sleeve? Does anyone know or know where to get the torque specs for this kinda job? thank you for your help!!
Slow down here, first the block and heads are cast iron, second the upper intake issue is far more common than hd gaskets, the egr passage in the uim burns through to the coolant passage and coolant enters the intake, this can hydro an engine, check this out before jumping into this tear down,. You need to diagnose the cause as best you can beore a tear down, so you know what to look for.

I took it to a local ase certified shop for diagnosis

IF you hydrolocked it, you could have a bent connecting rod, cracked head, or bent crank. BAD things happen when you hydrolock an engine. It's the old story of an immovable object (the coolant in the cylinder that can't be compressed like air) meeting an unstoppable force (the piston coming up on the compression stroke). Something has to give, and it's normally expensive engine components.

I took it to a local ase certified shop for diagnosis
Good, but how did they determine it was a hd gasket as opposed to the very common, as I said, intake manifold problem, Water in the cyl does not mean the hd gasket is bad, as Rich said if it locked up they must check for possible internal damage before spending any money on this engine, a compression test will reveal if the rod may have bent, but the root cause is still an issue.

if it is the intake gasket leaking by, I would have to change it out on the build up anyway wouldn't i? They found the problem with a compression test, and what it was narrowed down to a cracked cyclinder or head gasket, but i have to tear it down to find out which.

and if it is a cracked cyclinder do you know where to find a crate motor for the l36, i can find the l67 everywhere, but can't seem to find my motor

If you need to replace the long block or short block you can find a good reman unit for a lot less than a new crate engine, especially if all the other components are good. Send Ed Morad, moradpartscompany.com an e-mail. He specializes in Grand Prix's and should be able to get you a good used engine at a reasonable cost. If I were you I would pull the heads and find out what is going on. Based on what the others have said you may have a broken piston or bent connecting rod that is causing the compression issue. The head and cylinder may be just fine.

thanks for the help, its very appreciated