michael2e

Well time to revitalize this thread. Adrial, how did you resolve this problem? Did a retorque work? I've developed the same oil leak after 10000 miles on my rebuild. Like you, I did all the prep work and resurfacing as suggested by M42 before torquing the MLS and obviously it worked for quite awhile. Engine has been running well, conservative daily driving but the leak is definately below the cam tower exactly as you described. I have stock studs and did the 90 degree torque technique so I'm wondering if I should just try overtightening to 75 Ft-Lbs in sequence before biting the bullit and replacing the HG. Thoughts?

BTW, How to test the 'pressure valve' in the head? (And where is this?) Thanks

special tool

Why don't you just put a widefire and be done with it? Maybe you are just a few thou out of flat.
Widefire is very forgiving and absolutely no power limit.

Ian Carr

I have the cometic head gasket and arp head studs(shaved head and block). Every time the engine is cold (oil temp is below 200*) it will drop oil ONTO the cross over pipe . Makes a nice smell, but once the oil and water temp are up it stops. Only solution is to pull off the head. Again.. clean the head gasket sooo much along with the head and block and hope it doesn't leak...

When i first put my head on with the cometic it leaked antifreeze ..grrr

Then i got it to stop and now it leaks oil hahah.

adrial

I took the lazy, ghetto solution which was to slobber hondabond sealant on it.

It slowed it down but it still leaks a bit, one of these days I am going to retorque.

Asarus

Adrial, i got the same problem with the MLS headgasket and using copper spray. Both surfaces were machined by a pro, and the headgaket was correctly installed. I used brand new Porsche head studs

The leak came exactly from the same place (near the motor #sn)... i removed the MLS head gasket and put back a Porsche headgasket, no more problem so far...

Seb

OriginalSterm

650 miles on my Cometic and Raceware headstuds. Used sealant, and no visible coolant/oil leaks yet. No retorque yet either.

Asarus

2000 or 3000 kms (1500 to 2000 miles) for me before to remove it... i didn't notice the leak immediatly but it looks like it was there from the beginning. Maybe leaking more and more with time... ?

OriginalSterm

Hmmm...I will be going over the car with a fine-toothed comb this winter (after another couple hundred miles). Maybe something will develop? Hard to say right now, but so far so good.

michael2e

Thanks for the input guys. ST you're right, if I end up pulling the head I'd stick with a WFHG. So far the leak seems to be external causing annoying smoking when it ends up on the exhaust. Adrial, I dont know how you were able to get some sealant down there, I thought of trying that but cant reach around the valve cover. Other than having difficulty aligning the MLS gasket on the dowel pin, getting it to lay flush on the block, resolving an external coolant leak at the front and this little oil leak these are otherwise fine products.

951_VAB

Small external coolant leak intake side first cylinder on mine with new machined surfaces and new factory studs, Cometic MLS. Don't know if you guys know more of this but was common problem and Cometic supposedly changed design silightly this summer (July I guess.) Mine in new design getting ready to go back on with Racewares...
Dan

michael2e

Could there be a design flaw on the exhaust side of the #4 cyl causing poor sealing around the oil passage that mimics the problem on the front with the coolant passage? Sure seems odd that many of us have the same problems. It'd be something if Cometic stood up for it.

special tool

I don't know if it is a design flaw - so much as maybe Cometic shouldn't make it for the 951 because of narrow margins.
It seems that you really have to have everything perfect to get no leaks.

The widefire is very forgiving.

OriginalSterm

910 miles and a bit of a leak, time to retorque...

michael2e

Geeez! Coolant or oil?

OriginalSterm

coolant