Specialty RTV, ok to use for other purpose

[ford46guy]

I have a tube of the Permatex Gear Oil RTV. There is a round EGR tube that feeds into the intake. The hot tube is about 1/2 in dia and there is a insulating pipe of about 1.5" that contacts the intake with a doughnut gasket.

Factory had some RTV on the base of the gasket. I'm installing a new gasket, the service manual does not specify to put RTV but I think I'll do it.

Hate keeping around tubes of RTV, since they have a shelf life and harden after 2 or so years, and would rather not make a parts store run.

Wondering if the gear oil rtv can be used on an intake? Or is it better to bite the bullet and use the black. I know some RTVs have silicon that can attack sensors.

 

[09_GXP]

Specific RTVs have different properties so it would be a matter of comparing them. I use Permatex Right Stuff for every application and have never had an issue. It has a large temperature range, can stretch 500% before breakage, resists fluids, and is sensor safe.

https://www.permatex.com/products/gasket...gasket-maker-2/

 

[Chris142]

The copper rtv is for high temps.

 

[ford46guy]

Originally Posted By: 09_GXP
Specific RTVs have different properties so it would be a matter of comparing them. I use Permatex Right Stuff for every application and have never had an issue. It has a large temperature range, can stretch 500% before breakage, resists fluids, and is sensor safe.

https://www.permatex.com/products/gasket...gasket-maker-2/


Yes, its very good I used it on a lawn tractor transmission with a not so great flange, sealed perfectly. Only thing is the 5 minute work time, that turned me off to it. It was a very complex shape that took the whole can. Needed sealing internally and below the wheel bearings, so the shafts had to be reinstalled.

 

[FlyNavyP3]

I've always used the Ultra Copper for high temp installations.

 

[eljefino]

If you have a "squooshy" metallic gasket I'd just use that, plain. A "tiny" exhaust leak isn't the end of the world like something like oil or antifreeze leaking which could be the difference between "needing to check the fluid" vs not.

If you have a compromised mating surface then pursue RTV.

 

[ford46guy]

Here it is, notice the bit of RTV on the bottom of the old seal(already cleaned metal). Service manual don't mention it. The next year went to a different pipe and thinner o-ring, maybe they were having issues. This is the egr pipe that sends hot air into the middle of the plenum.

 

[ford46guy]

Bought a small tube of Permy Black, was like $3 with the discount, needed brake and maf cleaner too. If it gets hotter than 500deg I'll have bigger problems, the nylon intake will be melted. This isn't a metal to metal connection, and the egr heat is insulated with the outer tube for the plenum.