Must I use sealant on head gasket?

[whitebroncoii87]

I just spent some long minutes scraping old head gasket pieces stuck to my block after pulling out the heads. I assume this was caused by sealant?.. which leads me to think should I put sealant on? If necessary what kind of sealant is recommended, thank you!

 

[The_Epsicle]

I've rebuilt a couple engines and I've never put any sealant on, in fact I'm not even sure they make sealant for head gaskets considering the heat it would have to endure. The pieces you're scraping off are from the gasket, it expands and contracts during normal usage and when you pull the heads after a couple thousand miles some small pieces are going to stick. It's perfectly normal, I've had it happen on every engine I've rebuilt, it's just a pain to clean up

 

[Lone-Ranger]

^^True, that.^^

 

[adsm08]

Head gaskets are layered sheets of metal and the outer layer is impregnated with a silicone compound. They are in effect self-sealing. That silicone is what you are scraping.

I put a thin coat of spray-on copper exhaust silicone on head gaskets. It isn't necessary, it's just a bit of insurance since I usually am working on old engines if I have heads off.

 

[csargents1546]

I don't use an sealant on head gaskets. It actually creates the POSSIBLITY of a leak of some kind when the sealant degrades from the heat. A good clean surface and try not to touch the sealing parts of the head gasket. That is just my ocd when it comes to head gaskets. Cleanliness is essential.

 

[whitebroncoii87]

Oops I smeared engine oil all around it, kind of thinking itll do the brittleness of the gasket some good.. no idea if that was actually a good thing

 

[black_demon69]

rule of thumb for head gaskets is

1 good clean surfaces no oil or debris

2 no sealer of any kind

3 and follow proper torque procedure

 

[Lone-Ranger]

Im not sure what oil will do... Never heard of anyone putting oil on a head gasket. They are not intended to have any extra sealer anyway...

 

[enjr44]

Back in the "good old days" heads were pretty flexible and gaskets not so good so folks used copper sealer on the gaskets to prevent coolant leaks. Can't do that today with aluminum heads (copper eats aluminum).

Today, clean, clean and clean and put it together with Felpro gaskets.