I'm going to install a Titan hg soon, and I'm wondering about coating it before installation. Titan doesn't reccommend it, but has anyone on here done any precoating before install? ty
Headgasket coating question
- Thread starter NewWestSupras
- Start date
If it's a NEW MHG...do not use any kind of spray coating on it. The MHG has a factory coating already on it...a spray sealer can turn it into goo and the MHG may not seal as a result.
Do a search...this has been beat to death ::dead horse::
Do a search...this has been beat to death ::dead horse::
mustangman05 said:
If it's a composite or used MHG, that's fine...on a new MHG, no way. Every MHG maker specifically recommends against it due to what I said above.
Beat that horse. What is funny is I used the search function for cometic to read if there was any negative feedback on it. Cometic gave me 5 pages of results and I read that response dozens of times.
LOL, I have about 10 7m engines built with copper permatex on a brand new HKS mhg that says different. Never had a bhg since using the copper spray, some have seen 20+ psi. Where do you guys get this info? The viton coating is just not thick enough to seal properly on all deck and head surfaces. And I'm not talking about shellacking the crap out of it, just a light even coat on both sides. But hey, I don't want to beat the dead horse or anything. My own engine has 3 years, 4 different turbos, 100+ dyno pulls, and 25 psi many times, and now around 475 crank hp on the HKS 2.0mm mhg with Permatex copper spray. There is no copper buildup in my cooling system or any of the other cars, as someone said would happen a while back. They must have used the whole can or something.
suprarich said:
The RA on our blocks and heads is better then most shops can even do with their equipment. <7 RA.
I'm not getting on you about it personally, I'm just stating my experience. This is one of the "unsubstantiated rumors" that are on my pet peeve list, so sorry if I get all huffy about it. LOL You're right, it is not needed, but it seems to help and I have not seen any ill effects.
Well...here's one:
http://www.aa1car.com/library/2003/eb30320.htm
And here's another:
http://www.babcox.com/editorial/ar/eb70228.htm
Note this part under Installation Issues:
"Another installer error is using a sealer on a coated composition head gasket. "Some sealers will react with the gasket coating and turn it into goo," claims McKnight. "Our philosophy with Victor-Reinz gaskets is if a gasket requires a sealer, we will include it with the gasket. If no sealer comes with the gasket, it doesn’t need any, and no sealer should be used."
Key words: "Installer error"
Every manufacturer...all of them...say the coating of Vitron is put there to make the initial seal. And all of them have an RA spec to make sure that seal happens. The RA and the torque spec on the bolts or studs is the driving factor on ensuring a MHG seals...using spray to make up for not resurfacing the block is NOT recommended by ANY manufacturer.
The companies that make the MHGs have engineers that are pretty smart about this stuff. I will trust them over any hearsay on this forum...every time. You can use the spray if you want...if you recommend it here, you should also point out that it is not the way the manufacture intended the MHG to be installed.
Arron...I'm sure you know what you are doing. This may be a "pet peeve" you want to re-think.
http://www.aa1car.com/library/2003/eb30320.htm
And here's another:
http://www.babcox.com/editorial/ar/eb70228.htm
Note this part under Installation Issues:
"Another installer error is using a sealer on a coated composition head gasket. "Some sealers will react with the gasket coating and turn it into goo," claims McKnight. "Our philosophy with Victor-Reinz gaskets is if a gasket requires a sealer, we will include it with the gasket. If no sealer comes with the gasket, it doesn’t need any, and no sealer should be used."
Key words: "Installer error"
Every manufacturer...all of them...say the coating of Vitron is put there to make the initial seal. And all of them have an RA spec to make sure that seal happens. The RA and the torque spec on the bolts or studs is the driving factor on ensuring a MHG seals...using spray to make up for not resurfacing the block is NOT recommended by ANY manufacturer.
The companies that make the MHGs have engineers that are pretty smart about this stuff. I will trust them over any hearsay on this forum...every time. You can use the spray if you want...if you recommend it here, you should also point out that it is not the way the manufacture intended the MHG to be installed.
Arron...I'm sure you know what you are doing. This may be a "pet peeve" you want to re-think.
aaron knows his shit. the two people i would trust with building 7m's is him and jeff (jtamulis)... they've probabyl built more 7m's on here then anyone else. successful 7m's to add!
jdub said:
Using a "victor reinz" metal headgasket might be something you would want to rethink. Also, "some sealers" does not apply to Permatex copper spray with a HKS metal headgasket, I am sure of that. I had a HKS stopper mhg blow on the first engine I built for myself a long time back when I first got into the 7m. The sealing layer just looked very very thin. It seeped pressure into the cooling system. There is sometimes some slight erosion that occurs around the cooling passages that the surfacing does not completely remove, and also something that looks like imperfections in the original casting on many blocks. There are many things on a 7m engine that you will make you learn to take standard engine building advice with a grain of salt. I've had to insist on several things that most machine shops will tell you is not necessary. Like they said, the viton layer thickness is .001" (one thousandth) There are imperfections in most 7m heads and decks deeper then .001 reguardless of how smooth you surface it.
bigaaron said:
I guess the question is what made you use the spray to begin with? It's actually the opposite of me saying not to use the spray...I've researched it and found the manufacturers do not recommend it. And the spray will dissolve the viton coating (depending on how much you use). No offense, but I tend to stick with the manafacturer's spec.
CryoSlash said:
That is not in question at all, but if I had Arron build a motor for me (and I've recommended him to a friend)...I would specifically ask NOT to spray the MHG.
bigaaron said:
Ok...from the Cometic site:
"Check your dowel pins as they register the gasket and head into proper location. Replace worn or damaged dowels. The gasket mating
surfaces must be smooth 50RA or finer. Additional sealer is not required with Cometic MLS Head Gaskets. The outer layers of the
gasket are coated with a .001" thick coating of viton (a high temperature flouroelastomer)."
Why would Cometic say that? If the sealer assisted in the seal, wouldn't Cometic reduce their complaints if thay DID recommend it?
Show me a manufacturer that recommends a sealer be used and I will shut-up
jdub said:
I'm not disagreeing with you that it is not needed, and I appreciate the mutual respect we share.
I think .001 is just not a thick enough viton coating for the 7m in particular. Their recommendations would probably hold true for 99% of the headgaskets they make, but we all know the 7m kinda defies logic on certain levels.
Remember that Cometic sells gaskets with rivets in them that will cause a major failure if not removed by the customer. That = poor design in my book. People misinterpreted the 50 RA as meaning the Cometic headgaskets are "more forgiving", yet there have been several blown Cometic MHG's recently because of that misinformation. If they are more forgiving then who needs to surface the deck..... OH No!
That's a good tip on the lock tight!
The best thing is that we can talk about why we disagree and still keep it civil, then people can see it from both sides before they make their decision. I argue not just to be right, but to give the advice I feel will help people. If I'm wrong I have no problem admitting it.
I wish IJ was here ROFLOL
The best thing is that we can talk about why we disagree and still keep it civil, then people can see it from both sides before they make their decision. I argue not just to be right, but to give the advice I feel will help people. If I'm wrong I have no problem admitting it.
I wish IJ was here ROFLOL
This is my take on it. I have seen people try to use copperspray and permatex as a lazy way out. They think they can skip out on some prep work if they just swab on the sealer. Anytime we post about using an additional sealer other than the viton it should be stressed that it is not for getting out of all the work involved in preping the head and the block. If you can get the block perfect with out casting pinholes, and the head a mirror. Then I think the viton alone is enough. If the block after being prepared shows porousity and corrosion marks, then maybe an additional sealer should be used.