head gaskit leak weird, new hg, .002 block and head deck surface

[silver bullit]

Arp headstuds with moly lube torqued to 90 ft-lbs.
Car never ran, deck surfaces flat. Block is with in .002 and the head is within .003 (Still within spec).
Torqued in steps of 25-60-85, correct order.

No gouge marks in the head or block surface.
Car has a cosmetic head gasket and arp's i bought from extremepsi.

Both motor and head where never overheated and have alway been in my possession for years now. Always taken car of and i checked every square mm on the head and block.
Motor was rebuilt less than 6k. Head stocker off 100k one i had.

Head and block where cleaned then gaged to .00x
Here is the problem:

I did the procedure for the arp's correct. (dont mention this i install/reinstall these things weekly in know what i am doing)

After I installed these i then filled the car with coolant and squeezed all the hoses while checking for leaks.

Nothing, so i figure cool.

A week later i noticed a small amount of coolant on the ground i figure cool, i must have spilled some.

Clean it up.

Fast forward 1-1/2 month and a half
Squeezing the 2 big radiator hoses i get it to leak, out he back under intake mani through hg.
I am getting a puddle under the car, so i figure WTF...

I check everything, determine its coming from the block, above the turbo. Rip off the down pipe and check more. Noticed its coming from the head gasket, its just running off so i figure gotta be the thermostat housing.

Thermostats clean and dry so WTF...

I figure i dunno i take off the intake mani while motors stays in car. I notice its leaking down the back of the block.

Well this pos is leaking from the back under the intake mani.

I know i installed this correct so i dont know why its leaking.

He's the catch:
WTF
Weird thing is when ever i tight the radiator cap it leaks, when i loosen it, it slows/stops.
WTF


Is there a heat cycle the hg has to go thru to seal? I know the arps do but that has nothing to do with 10 bolts/nuts tighten to 90 ft-lbs.

If it was arps why is it leaking tightened?



I need help....

 

[v8killer]

man i got a 95 tsi i bought almost a year ago the guy said it had a miss to it and he can't figure it out wont start ! well i found sugar in the injetors ! i cleaned them then put them back in start the car and it runs smooth but when i pushed the clutch the motor made weird sound at the timing cover, so i pull the oil pan and found out the motor had crank walked but didn't hurt the block. well when i tore the motor apart i found that all the intake valves were bent and were hitting the pistons but ran smooth ! i rebuilt the short block and the head put a rebuilt 14b turbo on it with other goodies. i start the car up and hear this weird noise coming from the timing belt are so i figure the timing belt pulleys must be making a noise even though they felt good so i bought new ones put them on and it still made a noise but it comes and goes so i let it run and decide to drive the car well as soon as i get ready to back out i feel the motor lose power so i try to cut it off a fast as i can and the motor just locks up wont even crank ! now i have to tear the timing belt off and figure out if the head goofed up or the fresh short block that went together sweet ! so go figure......... i can throw junk together and it will run forever but if i plan and buy all new stuff, something will mess up or leak or do something it shouldn't ! just tear it back apart and you should be abale to see were it is leaking !

 

[v8killer]

also try retorque the studs and see if any are loose ususally were they are lose is were the gasket is blown or leaking !

 

[silver bullit]

also try retorque the studs and see if any are loose ususally were they are lose is were the gasket is blown or leaking !

I am gonna do this agian for the 3rd time but i dunno if this is gonna help, it did not he 2nd time i did it.

Anyone else?

 

[TjPhillips36]

Was the head and block decked ever, or did you just check it to factory specs? The block and head need to both be completely flat when a Cometic or OEM MLS headgasket is installed. Even if it's within spec it's always nice extra insurance to get it decked so your not stuck doing it again. If the ARP's were correctly tightened, did you check after a few heat cycles that the ARP's were still properly torqued down?

I would think your head deck is probably out of spec if it's leaking that bad it probably never properly sealed.

Also did you use any copper spray on the gasket? I always use it now and have not had one problem with a head gasket not sealing.

 

[silver bullit]

Was the head and block decked ever, or did you just check it to factory specs? The block and head need to both be completely flat when a Cometic or OEM MLS headgasket is installed. Even if it's within spec it's always nice extra insurance to get it decked so your not stuck doing it again. If the ARP's were correctly tightened, did you check after a few heat cycles that the ARP's were still properly torqued down?

I would think your head deck is probably out of spec if it's leaking that bad it probably never properly sealed.

Also did you use any copper spray on the gasket? I always use it now and have not had one problem with a head gasket not sealing.

The block was decked when it was rebuilt 6k ago, the head to.

The motor has never been started yet, i am asking cause it is leaking and not even been started yet.

 

[v8killer]

if you haven't started it yet i would tear it back down check it again then use some copper spray on the gasket thats on it now and try again, if its leaking and you haven't even started it then there is something bad wrong ! if it's coming from under the head gasket. either way you wont know till you tear it back down....... mine has sit for about 4-5 months becasue i got disgusted with mine when it locked up after i put everythig new in it but i'm going to tear back into it in a few days. Don't give up ! SO how many leaks around the head do you see......... if it's leaking in more than one it sounds like the head isn't going all the way down on the block !

 

[silver bullit]

Its on the block, its only leaking out under the intake mani side i cant seam to pin point it but is somewhere in the layers of the hg

 

[silver bullit]

Thoughts anyone?

 

[silver bullit]

Alright so i said #### it, i torqued the head down to 120 with the moly lube even though it states 85 with moly lube and 120 with motor oil.

I noticed that the leaking has slowed but it only has cut the leak in half.

I am still getting about a pint leaking through the cometic headgaskit under the intake mani on this never ran motor.

Help?

 

[Big Woo]

This will be hard to explain in text but I will try.

The Cometic and other MLS type head gaskets by nature have some compressibility. I.E. they will continue to compress after the torqueing process. This can be best shown by the following example.

I will use your stated torque values of 25, 60, & 85 ft/lbs

When everything is ready to torque your head studs, set the torque wrench to 25 ft/lbs and torque all head studs in sequence to 25 ft/lbs, wait two minutes (the two minutes is arbitrary) Leave the torque wrench set at the 25 ft/lbs level and in sequence torque all the head studs again. You will most likely find that they will all move or rotate again at the 25 ft/lbs setting. The center ones will move the most, and there will be progressively less rotation as you move away from center. This is because the “M” in MLS stands for metal, and metal by nature is malleable.

One procedure some follow when initially installing MLS type gaskets is to torque multiple times at the same torque value, in sequence until no further rotating of the fastener occurs before moving on to the next torque level. This process should be repeated until the final torque setting is achieved and there is no more fastener rotation.

If your head and block surfaces are flat, have the required surface finish, and the above procedure is followed there will be no need for gasket spray, copper spray, silver paint, hylomar adhesive, or anything else to seal your Cometic or other MLS type head gasket.

 

[silver bullit]

This will be hard to explain in text but I will try.

The Cometic and other MLS type head gaskets by nature have some compressibility. I.E. they will continue to compress after the torqueing process. This can be best shown by the following example.

I will use your stated torque values of 25, 60, & 85 ft/lbs

When everything is ready to torque your head studs, set the torque wrench to 25 ft/lbs and torque all head studs in sequence to 25 ft/lbs, wait two minutes (the two minutes is arbitrary) Leave the torque wrench set at the 25 ft/lbs level and in sequence torque all the head studs again. You will most likely find that they will all move or rotate again at the 25 ft/lbs setting. The center ones will move the most, and there will be progressively less rotation as you move away from center. This is because the "M" in MLS stands for metal, and metal by nature is malleable.

One procedure some follow when initially installing MLS type gaskets is to torque multiple times at the same torque value, in sequence until no further rotating of the fastener occurs before moving on to the next torque level. This process should be repeated until the final torque setting is achieved and there is no more fastener rotation.

If your head and block surfaces are flat, have the required surface finish, and the above procedure is followed there will be no need for gasket spray, copper spray, silver paint, hylomar adhesive, or anything else to seal your Cometic or other MLS type head gasket.

I torqued it 25-60-85-90-105-120.

I let it sit for 5 minutes and then went though the next step.

I re-torqued each one 3 times on each level it was torqued at.

I let it sit each different setting and retorqued it again, i even triple checked.

All of them where done in order.

Not to mention it is still leaking, about a pint or so overnight. BUT ONLY WHEN THE RADIATOR CAP IS TIGHTENED. It trickles a few drops left with the cap off over a week.

Head and block surface is within .002 and the surface finish was better than 50.

 

[Big Woo]

Well since I wrote my responce this morning, I have some concerns that it may not have sat overnight yet, or are you talking about what you have done so far?

In re-reading your original post I see you did this at least a month and a half ago. Is it still true that you have not yet fired up the engine?

When using the Cometic and most other MLS head gaskets most come with instructions like this:
If you follow the paper work that comes with the Cometic head gasket they reccomend to install the head gasket dry, and also reccomend a surface finish of 50 or better. Additional checks include ensuring that none of the rivets that hold the three layers of the Cometic head gasket together interfere with any portion of block or head. It is also good to veirfy that all of the embossments on the Cometic head gasket completely seat on both the deck surface of the block and cylinder head. You do not want any of the embossments protrude into, across, or through any water passage or void in either deck surface.

You may have a rivet interference issue, but the rivets on near number 1 & 4 cylinders, and your described leak is near 2 & 3 correct. It maybe the embossment problem I describe above, did you ensure that all of the embossments on the head gasket sufficiently cleared their respective block and head operings?

I am not sugesting anything here, but this is something I have seen several time over the years but. Are you sure the head gasket was installed the right way I.E. top, bottom, front, back? Please don't tell me it is not possible because I have seen it done, and well they leak that way.

 

[silver bullit]

Yep.

Still not fired though all i gotta do is fix this problem leaking, plug the harness in/solder a couple of wires and then put gas in it.

I did and it was good, how ever i will note i did not get any direction to install and as soon as the head gaskit was opened the top layer of the thing was kind of wavy. It would still line up with everything but unless you sat a book on it the top layer would not be flat.

THOUGH: i have had head gaskets like this and i know a few other people that ran them like this and it was fine.

I can see all 4 rivets outside of the surface, i know i put this on right.

I know you can put hem on backwards but i did not. I lined up everything, and the way this gaskit is made to contour to the oil drain passages especially in the middle and outsides.

 

[Big Woo]

Sorry for the stupidity related questions, but I had to ask.

I have never seen a head gasket leak after installing but before running, and have it be fine later, but I am not going to claim to have seen everything either.

The top and bottom layers of the Cometic head gasket are very thin when compared to the center piece. I am looking at one I have right now and while the outside layers can be seperated from the center layer (to the extents that the rivets will let it) both sides are quite flat except for the embossments.

If this was my car, or a customers car I was responcible for, the choice for me would be easy, Take the head back off and check everything out twice again.

Many people have used ARP head studs torqued to many differnt values, but water under no pressure or very little (from sitting in a contained area with a variable ambient temperature) should not leak from between two flat surfaces with a known good gasket, (heck a good used stock gasket will seal that) torqued to 30 ft/lbs.

It is also possible that eventhough you were told flatness specs of .002 & .003 that a low spot was missed by the machine shop. Many times places are in a hurry and just check flatness at one spot (most typically from cylinder 1 to cylinder 4 along the centerline of the bores. However there is no rule that says warpage has to be along the long axis of the block or head, and then only across the centerline of the cylinders.

 

[Big Woo]

Another quick question If you did not have the block and head surfaces milled, how did you clean and/or prepare them for the new head gasket replacement?

 

[Burnett03]

I don't believe your head or block is 100% perfect. If it was me i'd ditch the metal gasket and run an OEM compostite one. They are known to withstand over 500$ when used with ARP headstuds.

 

[silver bullit]

Sorry for the stupidity related questions, but I had to ask.

I have never seen a head gasket leak after installing but before running, and have it be fine later, but I am not going to claim to have seen everything either.

The top and bottom layers of the Cometic head gasket are very thin when compared to the center piece. I am looking at one I have right now and while the outside layers can be seperated from the center layer (to the extents that the rivets will let it) both sides are quite flat except for the embossments.

If this was my car, or a customers car I was responcible for, the choice for me would be easy, Take the head back off and check everything out twice again.

Many people have used ARP head studs torqued to many differnt values, but water under no pressure or very little (from sitting in a contained area with a variable ambient temperature) should not leak from between two flat surfaces with a known good gasket, (heck a good used stock gasket will seal that) torqued to 30 ft/lbs.

It is also possible that eventhough you were told flatness specs of .002 & .003 that a low spot was missed by the machine shop. Many times places are in a hurry and just check flatness at one spot (most typically from cylinder 1 to cylinder 4 along the centerline of the bores. However there is no rule that says warpage has to be along the long axis of the block or head, and then only across the centerline of the cylinders.

No i was simply stating the way the head gasket was warped?(whatever its called) new out of the box and installed on other cars ran fine and had no sealing issues.

Its my car.

I checked every 1mm of the head and block surface. With a straight edge.

Another quick question If you did not have the block and head surfaces milled, how did you clean and/or prepare them for the new head gasket replacement?

I did when they where rebuilt. I checked every mm of that head and block.
Gasket scraper and some cleaner.

I don't believe your head or block is 100% perfect. If it was me i'd ditch the metal gasket and run an OEM compostite one. They are known to withstand over 500$ when used with ARP headstuds.

You got a link for the oem composite one cheap? No ebay!

I only wanna run metal cause i plan on running more than 30 psi this summer.

Heres the 411:


Head came off a rebuilt motor with 100k on it, had .002 on it i know i feeler gauged it and built it and ran it.

The block has maybe 6500 miles on it, fresh rebuild that i did and feeler gauged it.

Both where never over heated and have both been in my possession, NO ONE, EVER, drove my car/motor but me.







I am about to give up on cometic. Me and a couple of of locals here are in the same boat.

I have had so many problems with there parts, shity boxes with busted head gaskets, and dumb customer service that tells me i dont know what i am doing.

I build motors and race them, shit i even run the train at the junk yard. I am shocked with all the parts/cars i got i dont open a junk yard.

 

[silver bullit]

Well a few days ago i re torqued it to 120 and its still leaking. Leaks a little slower but i still am leaking the same amount.


Any suggestions?

I guess it is time the head comes off to send the head gasket in for a replacement.

 

[silver bullit]

Took the head off and like i stated i put the head gasket on right, torqued right, looked at the gaskit and it is not sealing right so i am gonna have to get this sent to them to replace it.


Any other suggestions?

 

[Burnett03]

You got a link for the oem composite one cheap? No ebay!

I only wanna run metal cause i plan on running more than 30 psi this summer.

.

I'm doing a motor build right now, and plan on running 30+psi on a 60-1. My headgasket choice was a composite straight from mits. (jnztuning.net) and Arp head studs.. I'll most likely copper spray the gasket too. I've ran 29psi on a composite with no issues, and other people have run over 30psi. Composite makes up for a head or block that isn't 110% straight. if you are set on a MLS headgasket, go factory mits. and don't look back. I've heard to many bad stories about cometic, and now i've heard another with your issues.

 

[silver bullit]

Yep i figured i was f'd when i bought this thing.