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Head gasket sealer

17K views 16 replies 11 participants last post by  DanH 
#1 ·
Does anybody have any bad or good experiences using a sealer with the head gasket? We are gonna use permatex copper spray-a-gasket.
 
#5 ·
Unless the gasket is imprinted with sealer on it then a couple of coats of silver or copper spray paint is as good a sealer as you can get. I spray the gasket with a light first coat - let it set - then give it a heavy coating. Do both sides and then torque it down in stages of 10-15 ft. lb. increments.
Here is the process I use when torquing heads or intakes:

My torque process is lengthy and complex but I never have to re-torque nor do I have trouble with leaks or blow-outs.
Tighten all the bolts in sequence (from the middle out) to 30 ft lbs.
back them all off in sequence completely.
Torque them in sequence to 20 ft lbs - going back to the first ones and redoing all of them beforegoing on to the next bolt. (1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 2, 3, 4, 5, and so on)
when you have all the bolts to 20 then follow the same proceedure torqueing them to 35 ft lbs, 50 ft lbs, and 70 ft lbs.
You should be able to go over all the bolts and not have any turn at all with your last setting.
 
#8 ·
Ask the gasket manufacturer. And NO, you cannot use sealer on EVERY type of head gasket. That's BS.

Cometc:
Cometic Multi-Layer Steel (MLS) head gaskets go on dry because they are coated with a sealant. Each MLS head gasket is coated with a .001" thick viton rubber that is bonded to the outer stainless steel layers. Adding an additional sealer can hinder the performance of an MLS head gasket.

Edelbrock - recommends Felpro and install dry

Mr. Gasket MLS: IMPORTANT: THE GASKET MATING SURFACE BETWEEN ENGINE BLOCK DECK AND CYLINDER HEAD MUST BE A SMOOTH 10-30 RA (AVERAGE ROUGHNESS) SURFACE. DO NOT USE ANY TYPE OF GLUE OR SEALER ON MR.GASKET MLS HEAD GASKETS. A SPECIAL HIGH TEMPERATURE COATING USED ON THE OUTER LAYERS OF THE
GASKET IS SUFFIECIENT TO PROPERLY SEAL GASKET


SO - unless you are using a copper or steel shim gasket, DO NOT use a sealer unless the gasket maker SAYS SO. Any other method will guarantee problems.
 
#10 ·
Ask the gasket manufacturer. And NO, you cannot use sealer on EVERY type of head gasket. That's BS.

Cometc:
Cometic Multi-Layer Steel (MLS) head gaskets go on dry because they are coated with a sealant. Each MLS head gasket is coated with a .001" thick viton rubber that is bonded to the outer stainless steel layers. Adding an additional sealer can hinder the performance of an MLS head gasket.

Edelbrock - recommends Felpro and install dry

Mr. Gasket MLS: IMPORTANT: THE GASKET MATING SURFACE BETWEEN ENGINE BLOCK DECK AND CYLINDER HEAD MUST BE A SMOOTH 10-30 RA (AVERAGE ROUGHNESS) SURFACE. DO NOT USE ANY TYPE OF GLUE OR SEALER ON MR.GASKET MLS HEAD GASKETS. A SPECIAL HIGH TEMPERATURE COATING USED ON THE OUTER LAYERS OF THE
GASKET IS SUFFIECIENT TO PROPERLY SEAL GASKET


SO - unless you are using a copper or steel shim gasket, DO NOT use a sealer unless the gasket maker SAYS SO. Any other method will guarantee problems.
have you used all those types of gaskets ? when you have , will know what real BS is.
 
#11 · (Edited)
I can't understand why a lot of you guy's and almost ALL Chevy guy's use Permatex and RTV ON TOP OF GASKETS??????


A GASKET is there to mate two different pieces together (whether similar metals or plastic to metal or otherwise it matters not) and provide a SEAL. Else-wise my fine feathered friends closely related to the now Extinct Dodo Bird, it would NOT be called a Gasket now would it?

I never use spray on gasket or silicone or RTV or Permatex to make a Gasket seal. Gaskets SEAL all by them selves... (only Exceptions are where I use JV8 RTV on my intake manifold ends and main bearing corners, or other natural deviations that would prevent a continuous even pressure to the mating surfaces)

ALL of my engine builds PROVE this beyond a shadow of a doubt....

So why the spray sealer on anything but metal gaskets is beyond me.
 
#13 ·
Copper spray sealer works great on MLS gaskets. Have had minor sealing problems with un-coated MLS gaskets but since using copper spray all sealing issues have been solved. This is on a 14.5:1 race engine that lives at 7000 rpm. Yes, I know what the MFG. states but in the real world the copper spray works best. Oh, and yes the block and heads are prepared properly with the correct finish.
 
#14 ·
Copper spray sealer works great on MLS gaskets. Have had minor sealing problems with un-coated MLS gaskets but since using copper spray all sealing issues have been solved. This is on a 14.5:1 race engine that lives at 7000 rpm. Yes, I know what the MFG. states but in the real world the copper spray works best. Oh, and yes the block and heads are prepared properly with the correct finish.
+1..
I had problems with the cometics seeping and should have used some copper spray on them...
 
#16 · (Edited)
Yes I have - and I follow the mfg recommendations. If the decks are prepped properly there will be no sealing issues. I mostly use FelPro Blue series performance gaskets on the heads, installed dry and they seal very well, thanks. It's a bit surprising that you think the companies and engineers that spend the energy developing these items don't know what they are doing.

My personal opinion is that if you are having sealing issues with a gasket that is engineered to be self sealing, there is some other problem - surface finish, contamination, flatness, etc - that needs to be addressed.

The major problems I see and read about with the MLS gaskets is surface finish. In some cases, it has to be so fine that many shops can't get there. Do a little googling, you'll see plenty that a lot of shops can't hold surface tolerances the way the factories can.

Here's an exception for that:
http://www.ertyu.org/steven_nikkel/neontsbs/2000/09-08-99.pdf
 
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