Continuos head gasket problems?

[GRNDSM]

I am not 100% sure what is the best gasket available at this time. There are our choices:

Stock composite gasket: many people have good luck with it up to 30psi. BR swears by it on all of their cars, only they use it with O-ringed head. The tricky part is that block and/or head has to be o-right JUST RIGHT for the specific type of gasket that you are using. So if BR can achieve a perfect seal with THEIR o-rings and stock gasket, does not mean that any other shop will be able to duplicated it…

Mitsu multi layer: again, many people use it with great results.

Cometic: fairly new to DSMs, but has pretty good track record on other cars. Looks like a better quality Mitsu multi layer gasket. The problem that I see with Cometic gaskets, is that they require a VERY SMOOTH surface to seal well (this according to Cometic tech support people). Many machine shops might not give you good enough surface finish to assure that Cometic gasket seals. I am not 100% sure, but I would imagine that Mitsu multi layer gasket would have a similar issue.

Copper gaskets with O-rings: not very popular in DSMs.

HK$… way overpriced, I do not know anyone using them…

On my next motor, I am going to use “very fine” surface finish on both head and the block, together with Cometic gasket. If it fails again, I am going to ditch Cometic gaskets and go to something else.

Leon
RR

 

[gritsak]

aight so after reading through this and a thread on dsmtalk...what about this setup...

since i have an o-ringed block, the mls headgasket isnt ideal...so how about just playing it balls and putting in a new oem composite w/copper spray on a fresh resurfaced head torqued down with arp's ...as mentioned many top racer run it (although also mentioned im sure they have their own secrets/tricks on doing it right).

on my car ive got an fjo wideband and a datalogger so i can tune it really well with accurate numbers on a/f and knock...and it will be run on 114octane most of the time anyways.

so how does this setup sound? ive gotta get this motor back together soon so i have to decide

 

[MNGSX]

I'd ring the head too.

The seal is the weak link in the chain. To get the full effect of an o-ring both sides have to have it. Head and block.

For that my suggestion is a dead soft copper gasket. Just a slab of malable copper that will readily conform to the o ring groove when tightened.

 

[gritsak]

aight so ive been reading the nabr tech archives for quite awhile now and came up with another option that has seemed to work for others in a similar situations....use copper for the o-ring and get it so it seats about ~.008" above deck height..then use a factory metal head gasket sprayed with copper...so when you torque it down, it will smash the copper ring to get a good seal and not interfer with any of the other seals on the gasket.

this seems like the best option so far for me...i dont want to use a copper headgasket at all...i just dont hear about hardly anyone having luck with them or even running them for that matter.

i dunno..im really to the point where im just going to try something and see how it goes..theres so many different ways to go about it and lots of different people having luck with different setups its hard to figure out whats best without trying

 

[QuickerDSM]

Well, I said I would update you guys on my HG/Copper gasket spray method so here goes:

After my head gasket completely let go about a month ago, I decided to run the Mitsu MLS steel HG with ARP head studs and I used the Permatex copper gasket spray on both sides of the gasket. I used the Copper spray on the advice of a local DSM tuner in my area. The idea is that the metal on metal contact doesn't produce a 'water tight' seal under extreme cylinder pressure. The copper spray makes a nice seal between the deck/gasket/cylinder head. I used about 3 mild coats of the spray on each side of the gasket and let it set for at least 5 minutes between coats. Other than that, just the normal stuff install with the ARP head studs. I used ARP's recomended torque values and moly lube.

So far I've been running 16psi daily (big16G + normal bolt-ons) for about 2 weeks now. Before the gasket blew, I was pushing oil into the coolant. Now the oil pushing problem is completely gone! I've been running the car fairly hard on a day-to-day basis and I've been very happy with the results. I know 16psi isn't a lot of boost, but before the end of summer I want to push it to 20-21 with some C16. We'll see how she holds then.

Mike

 

[ellsjer001]

GRNDSM this might sound weird but if your blowing head gaskets and dont know why, here is a little something to check. take a fluke meter(volt meter) check your coolant for voltage if you have close to or over 2V then there is acid eating away at your gasket... just a suggestion!! if there is then check your mounts for your radiator, make sure that you have rubber mounts between the frame and the mounts.

 

[hose101772]

Well I had good luck with a felpro for a year.Running 20lbs w/ compression @205lbs cold.Leaked after a month,blowing coolant out of overflow.Retorqued the arps,100ftlbs fixed it.Worked fine for rest of the year till I loosened up the knock sensor,well worked really good after.Then I had to buy fuel at a place I knew better than to but thats a different story.Block and head were decked when I put it together,both destroyed now,of course.Could have been luck I guess but after seeing what a cheap headgasket could hold,I wont be putting any engines together without having both surfaces decked.

 

[GRNDSM]

FelPro, makes pretty good gaskets, but they do not work very well in DSMs!!! Many fast DSMers have tried them with the same results: THEY FAILED !!!

I would highly adivise to stay away from it!!!

What boost power has it seen so far? It might be OK if you keep it under 300-350hp.

Leon
RR

 

[hose101772]

It died a horrible death-part of sealing ring came out back on head/deck surfaces,killed a set of j&e's,burnt material away on block and head.Pretty much it all went at once on all cylinders but #4 chucked the sealing ring out.I was running a b16g so I dought it ever seen much more than 300 but it did have way high compression(205 cold) running it at 20lbs.Lasted a full year(very hard 12k miles) with the boost at 20 so I cant say theyre junk or anything.I guess it would have been fine but loosened my knock sensor a week or so before it blew.Had just filled up about 4 miles before.<-badddd gas.Warning-do NOT screw with knock sensor.ol.Anyway with both surfaces decked,a retorque after several heat cycles,even the cheapest gasket held up well.

 

[nolv4v8]

Sorry to bring this back from the dead, but I was wondering what the final consensus was? I am building my motor and it is time to buy the head gasket and I am torn. I am leading towards the cometic because I see Magnus sells them. GRNDSM, what happened with you, seeing as I have the same turbo and a similar setup after the built motor?

 

[rforres]

just had a cometic hp fail after only a week, any updates on this thread, it was on a fresh motor ...

 

[GRNDSM]

Was the deck on this motor decked? How about the head? Was it "shaved" and if so, how smooth was it?

Leon
RR

 

[Amar1995]

I am working with a guy that wants me to use a metal head gasket, and then here is the wierd part, for the o-ringing he makes the indentation in the block square in shape and then uses round copper wire in the square indentation around the cylinder. He uses Cometic head gaskets and they do have a Dyno proven DSM with over 600 hp on this set up. My car is going to be used on the street and strip, but not a daily driver. I know it is easy to make a "Dyno Queen" but what do you guys think of this set up? I was very confident in it untill I read this thread If you would like to see his set up here is his car: Just scroll down on the pagehttp://www.f2uning.com/pages/9/index.htm

 

[rforres]

Originally posted by rforres
just had a cometic hp fail after only a week, any updates on this thread, it was on a fresh motor ...

this is a reply to leon, 2 post up ....



head was resurfaced , not sure about the deck,a trusted machine shop did the long block, i removed the head sent it to a shop that only does head repairs told them my problem and they suggested a pressure test and check the surface for flatness and squareness, everything checked out ok, i called cometic and they want me to send them the gaket for inspection, the deck looks good except for some very MINOR pitting right near the edges, im going back w/a mitsu mls hg and copper spray this time, when tuned i will be around 28 psi on race gas and a wet kit, hope it holds, THE ONLY THING I FOUND OUT OF THE ORDINARY WAS 3 STUDS WERE FINGER TIGHT AFTER I REMOVED THE HEAD, this could of happened during removal of the nut as i used an impact wrench, but im not sure. i will be loctiting them in this time .the cometic gasket did have some of the viton coating missing in a section and cometic said that was usually indicative of head movement .

im doing the 272's i had sitting and the mitsu gasket right now, im really lost and frustrated having to do this after a week on a motor ive spent so much $$$$$$$$$$ on .

ill update tuesday night after i get back for the track


leon, did u figure out your problem ?

 

[ecr1055]

go to your dsm parts guy and spend 60$ on a mitsu metal head gasket. Works great and handles lots of boost and hp. Felpros suck ass for dsm's...

 

[GRNDSM]

My problem goes back quite some time, I had 4 different heads/gaskets/blocks combinations in last year:

1st (ever over 6 years of racing) blown HG: 100k miles block, stock HG, used head, mixing oil in coolant, but no other problems!

2nd blown HG: same block, stock HG, machined flat head. Pushed coolant almost immediately with very little boost (17-19psi) on race gas. By all accounts, this shouldn’t have happened. At first, I suspected the block, but it measured perfectly flat. Now, I am thinking that I might not have bled the cooling system right…

3rd blown HG: freshly rebuild/decked block (not very smooth), freshly machined head (very smooth) and high boost Cometic HG. Blew after 10-20 ¼ mile passes running 26-28psi. It was very clear that it blew on the block side (carbon). The head side was pretty much perfect.

Conclusion: this block was too rough to be used with Cometic HG. Cometic tech support confirm it.

4th HG. Same “rough machined” block. Same smooth machined head. Factory composite HG. Boost 29-33psi for 30+ passes and still going strong.

At the end of the season, I thought I had nothing to loose so I tried running boost considered unsafe for composite (stock) factory gasket. But it still survived.

Basically, I confirmed what I have heard all alone, metal HG’s require VERY smooth sealing surface. I have no reason to believe that Mitsu 4 layer metal HG is any better than Cometic in this regard.

In all cases, I used ARP head studs torqued to 95 lbs*ft with ARP lube. Re-tightening the nuts made no difference as I couldn’t get them to move even under 100 lbs*ft, just a week later…

So I guess you can say that “fixed” my problem by using stock HG .

But on my next motor, I am going to use a smooth deck with smooth head and Cometic HG. If it fails again, I will drop it for good .

>Felpros suck ass for dsm's...

I have never tried them myself, but that is because I have seen DOZENS of people blowing their HGs at very conservative boost levels. But this was years ago, unless they drastically changed their HG, I would not even consider use it on my daily beater…

Leon
RR

 

[rforres]

Originally posted by GRNDSM


Conclusion: this block was too rough to be used with Cometic HG. Cometic tech support confirm it.

4th HG. Same “rough machined” block. Same smooth machined head. Factory composite HG. Boost 29-33psi for 30+ passes and still going strong.

At the end of the season, I thought I had nothing to loose so I tried running boost considered unsafe for composite (stock) factory gasket. But it still survived.

Basically, I confirmed what I have heard all alone, metal HG’s require VERY smooth sealing surface. I have no reason to believe that Mitsu 4 layer metal HG is any better than Cometic in this regard.

In all cases, I used ARP head studs torqued to 95 lbs*ft with ARP lube. Re-tightening the nuts made no difference as I couldn’t get them to move even under 100 lbs*ft, just a week later…

So I guess you can say that “fixed” my problem by using stock HG .

But on my next motor, I am going to use a smooth deck with smooth head and Cometic HG. If it fails again, I will drop it for good .



Leon
RR

i will try the mitsu metal w/copper spray, if that fails i will switch to a mitsu composite, i liked the idea of the thicker mls beacause of the 9.0 wiseco's.

 

[JAYTEE]

Lots of interesting info relating to head gaskets and their effectiveness. It
would seem that there are a number of ways to seal the head to block
interface. Experience has taught me to leave a slight machined finish on
the head and block surfaces and spray whatever head gasket you choose, liberally, on both sides, with Copper Kote. This sealer has a
quantity of copper dust in it which fills and seals the surfaces.

 

[GRNDSM]

Which gaskets are you talking about here? Metal or composite?

Leon
RR

 

[BUCK]

Most of you guys know better - but how many guys out there aren't cleaning the bolt threads - aren't tapping the holes in the block - aren't then vacuuming the holes in the block - aren't using proper sockets or bits - aren't adding the running torque of the fastener to the final specified torque - aren't using anti-seize on the threads, etc, etc...

You can face your block & plane your Head all you want to but if your torquing some rinky-dink Chinese bit instead of the fastener into a dirty hole...

 

[JAYTEE]

Hi GRNDSM,
I have used Copper Kote on composition and steel head gaskets for
every engine I have built, since I was introduced to it in 1969 or 1970.
Before that I always sprayed them with silver paint. This was for all
engines including Chevy, Ford, Chrysler, MG, Mitsubishi, and Toyota.
Many of these were turbocharged or had up to 13:1 compression ratio.
In addition many of the engines were used in marine applications. I have
never experienced head gasket failure that was not associated with some other major problem such as detonation, overheating, etc.. I am
not writing this to say yippee for me, but rather to express my belief in
Copper Kote on both sides of the gasket.
JTT

 

[GRNDSM]

A factory DSM head gasket effectively has a “silver paint like” material on the outside. Ever tried cleaning up the HG surface after removing one of those gaskets? I firmly believe that OEM composite HG does not need any additional spray and it seems to be working just fine now.

I know what people say about rougher surface for the composite gaskets (like Mitsu OEM), but I believe that metal gaskets (like Mitsu 4 layer or Cometic), require VERY smooth surface. I will say it again, Cometic tech told me that I can’t have it machined too smooth for their gasket’s liking... The smoother the better!

Clearly, Mitsu composite HG likes the rough surface

BTW, I too, never had any problems with my HG’s (I started racing DSMs in ‘95), when I was running upwards of 400-450whp, middle of the race season 2002. And I was racing A LOT in that period of time, on an average, I would do: at least 100 1/4 mile passes, 8-12 AutoX events (4-6 runs each), 3-4 oval track races and spirited street driving on pump gas and 20psi .

And then, all of the sudden... The only thing that I have changed was turning my car into a trailer queen .

Leon
RR

 

[jpolizo]

Well, just to throw in one more data point -- I put in a Cometic when my head gasket failed; it leaked.

For the dirty details: I went with a ported head and it was smooth as heck. I did not have the block decked but I did check it with a straightedge and it was fine, near as I could tell. I cleaned the block with a scraper and solvent and it was very smooth to the touch but I did not machine it or use any kind of abrasive.

I applied three light coats of Permatex copper spray to both sides of the gasket. I used ARP studs and torqued to their specs using their moly-lube.

The first run of the engine was fine, no detectable leakage. When I shut the engine down, allowed it to cool, and opened the radiator there was no pressure in the radiator. The second time I ran it, however, I started seeing bubbles in the coolant reservoir. After shutting it down from the second run, and allowing it to cool, there was a lot of positive pressure in the cooling system.

I retorqued the studs but that didn't solve the problem.

In a nutshell, I got skunked. I'm going back to the composite OEM gasket.

 

[MNGSX]

I run an OEM gasket now.

Engine two will be dead soft copper note not MLS. I won't have room between the slugs for a OEM style fire ring .

I'm oringing the head and block. On the block and head we are going to put a ring around every coolant and oil feed passage in addition to the around the cylinder sleeves. Ever see the marks on a copper washer for a banjo bolt? What happens is the dead soft copper head gasket compresses since the grooves dont squeeze as hard as the flats it forms perfectly matching rings sealing the parts.

 

[gritsak]

Originally posted by MNGSX
On the block and head we are going to put a ring around every coolant and oil feed passage in addition to the around the cylinder sleeves. Ever see the marks on a copper washer for a banjo bolt? What happens is the dead soft copper head gasket compresses since the grooves dont squeeze as hard as the flats it forms perfectly matching rings sealing the parts.

ive thought about that..it will be alot of work, but worth it if you dont have to mess with the head gasket again. ive seen extremely high HP motors (domestic) that use all copper o-rings to seal off the head and block, without the use of any type of "gasket".