ATTN: All QUALIFIED CA techs...

[float_6969]

I think whoever did your block and head work screwed something up. It sucks, but I think you need to pull the engine and have it re-done.

[mmm240]

This thread does not deliver.

[ilovecoupes]

This thread does not deliver.

doesn't deliver what?

[mmm240]

doesn't deliver what?

Answers

[davidricardo86]

Wow i had no idea this problem has been going around in the CA fourms for a while! A lot of people have had problems with their headgaskets and the culprit seems to be these "fault" Cometic HG. Im also one of the many that installed ARP head studs and Cometic MLS HG so this worries me. I did have my machinist deck the block and head and told him i'd be running a steel gasket.

Im going to do a compression test and post back the results. I'll check for oil leaks around the block/head too and let you know what i find.

[Not_a_sr]

Answers

Sure it did, there were plenty of good answers in this thread, the main one being is know what you are doing when replacing a head gasket. the leaks are often user error, and also machining errors, i have installed dozens of these with only one customer having a leak and it was DIY install he ended up bringing me the car because of the leak and it was a machining error due to him not giving the shop the front cover and it being 5 thousands to tall so the head sat on it and not the block surface.

I am installing another cometic on a SR in about 4 hours lol it wont leak either.

[MeanGreenS13]

yeah guys, use your heads. why would a head gasket just... LEAK for no friggin reason. if you honestly believe that, your out of your frickin mind!

like i said it wasnt the head gasket, caus eeven with a felpro, i have a leak.

[niscort]

so it still leaks with no reason as to why?

fwiw quite a few, if not all of the head bolt passages in the head become pressurised... thus it wont only leak from the oil drain holes in the head gasket. quite possibly coming from a headbolt hole.

[MeanGreenS13]

i put thread sealer on all threads haha

[niscort]

i put thread sealer on all threads haha

you realise this will ultimately affect the torque settings right? you will reach the required standard setting long before the bolt reaches the correct clamping force as the sealer will create a greater friction on the threads.

Let me guess, you did the same when you torqued the cosmetic?

Thread sealer, for what ever reason you used it????, will only seal oil from coming up from the block. which it doesnt, as I mentioned before, the passages through the head in which the bolts run become pressurised... this comes from the head.

[MeanGreenS13]

they are arp studs and the thread sealer is only where the stud threads into the block... i would never do any different seeing as it goes into oil passages... it should effect Tq

[davidricardo86]

Hey meangreens13 did you ever figure out what was wrong? How did you remedy it?Heres my test results:1 145psi 2 155psi 3 150psi 4 155psi The numbers are lower than normal but not yet at the minimum according to the fsm.

[ruckus-racing]

throttle plate open engine at operating temps? did you try pouring oil into the cylinders?

Jon

Hey meangreens13 did you ever figure out what was wrong? How did you remedy it?Heres my test results:1 145psi 2 155psi 3 150psi 4 155psi The numbers are lower than normal but not yet at the minimum according to the fsm.

[AFSil80]

Hrm, I'm just now seeing this thread, and I'm looking at a 2mm cometic HG and a box of ARP studs on my desk...

BOTH my head and block have been to the machine shop, so I'm sure the surfaces are good.

As for torque down...I don't recall reading in ARP's install directions to do a 'staged' torque down ranging from 25-80 ft/lbs.

eitehr way...i'll post up my thoughts on mine in a week or so...

[davidricardo86]

throttle plate open engine at operating temps? did you try pouring oil into the cylinders? Jon

Yeah i had the throttle plate open. I didn't use the oil trick, its a fresh engine so i didn't think about it. The engine was warmed up but i don't have actual temperature readings.I was thinking about retorque-ing the head studs.