i recently put a new head gasket in my blacktop SR and everythign was running fine no leaks motor cran good. yesterday i was on the highway and i was going about 120 cruising and the HG let go and oil was pissing out from the back of the head and i lost compresion obviously. MY QUESTION IS DID ANYONE HAVE THIS PROBLEM WITH THIS TYPE OF GASKET OR IS THIS JUST A ONEW TIME THING. THERE WAS 1000 km ON THE HG AND I WASN’T EVEN IN BOOST AT ALL. JUST WANT TO KNOW IF ANYONE KNOWS ABOUT THESE COMETEC HG AND IF THIS IS COMMON
I’ve heard it leaks if you don’t use copper sealer, despite cometic saying you don’t have to use anything.
I’m sure someone with more experience with this piece can shed some light on the story.
i did use a sealant on the gasket for extra support but that wouldn’t matter i don’t think. this thing just blew like nothing completly no compression and oil burning out the exhaust like crazy if it was a leak becasue of the sealant it would of just leaked out slwoly and the motor would still run fine.
did you use factory head studs… maybe they were stretched beyond specs?
i used arp head studs
EUE?
What did you torque them to and what method did you use?
did you have the head decked?
Did you have the head re-surfaced? The cometecs are very finicky(sp) peices.
Cheap option Cheap results… sorry not tring to be mean just blunt.
A ton of the CA people on NICO have had issues with cometic gaskets.
Most of it had to do with the decking of the head and block being done poorly or the nuts used with the arp studs compressing too much.
word,
i had a problem with a supposed unused cometic but the problem was the head.
i had it decked the next day and put on a brand new cometic with ARP studs and its holding up against some pretty heavy $hit.
to be honest, i wouldnt use any other gasket
Apexi is supposed to be the best headgasket, greddy the worst
ive heard its 50 50 chance with cometic
general concensus on metal headgaskets in my research seems to be that you need to o-ring the block and groove the head for copper, and use some kind of (copper?) paste sealant for steel, unless it’s a crush gasket
and yes, your dimensions have to be dead on, paper and composite gaskets can make up a few thou, metal won’t
I think oringing the block is overkill. Most people wont be running 30psi.
If you clean your block and have a flat head than metal headgaskets work just fine, I have been using them for over 5 years now with countless rebuilds and they have held up just fine.
99% of the time its user error.
i had the head machined. and what do you mean by o ring the block.
they cut a small grove around the outside of the cylinder and install a very small o ring to makesure that it seals really well. expensive.
i had the head machined. and what do you mean by o ring the block.[/quote]
I suspect you have an installation error somewhere. Even if it wasnt sealing well you wouldnt have the amount of leak that you do. Tear it apart and go from there.
I doubt he wopuld have an instalation error.
Sorry to hear about the bad luck, i was really anxious to see how it turned out for you.
Hope you can get it fixed up with the new gasget…
i’ve done a head gasket job on many different vehicles. sr’s arent different yes i am not perfect it might of been an installation error. i guess we just have to see its gonna be running saturday again for sure. i have a power enterprise gasket now. lets see what happens. thanks for everyones help
You did the head yes, but did you do the block. Metal head gaskets are tempermental. CA guys have stupid amount of problems with them, when they don’t deck the head and block. The CA is more picky than the sr though due to the iron block and aluminum head, different expansion rate. Did you loosen the arps then re-torque them? If you don’t back them all off and re-torque them you can run into problems with the head gasket. Thats what all the techs say at work (nissan) so I always follow it and never had a problem.