gasket sealing compound or not

[getitrunning]

just wondering what others think about using gasket sealing compound, gasket sealant, form a gasket or RTV on surfaces such as final drive covers after getting surfaces good and clean and buying or making a new gasket. I usually lean towards using the brown stuff that cleans up with alcohol that won't let water, fuel, or oil through the mating surfaces, the stuff used in aircraft and outboards from my past being an omc and Yamaha outboard motor mechanic.

 

[Glen]

Hi,
I use Permatex Aviation Form A Gasket for the final drive covers. It is a non hardening liquid.
It comes in a small can with a brush under the cap. NAPA sells it in my area.
I would use the gasket too, put the sealer on both sides of the gasket. A thin coating is enough.
Check the pans with a long straight edge to be sure they are flat where the gasket goes.
Hammer them flat if they are bent at the holes, or other places.
Below is a picture of the sealer.

 

[ricky racer]

I'm certainly not a fan of using RTV silicone sealant for gaskets which I see many guys use. If I use a gasket sealer, I use it very sparingly and will usually use Permatex Form A Gasket as Glen mentioned above or Permatex High Tack. A friend of mine swears by Yamabond which you probably used as a Yamaha mechanic.

 

[JohnMihevic]

I use Permatex Ultra Black Gasket maker that's made to seal out oil. You can use it with a gasket or without. You apply it to the surface as a bead 1/16" to 1/4" thick. tighten all bolts only finger tight -- until you see some the Permatex squeezing out. Let sit for 1 hour. Then torque bolts to spec.
It works great.

 

[Matt Kirsch]

I use a light smear to hold the gasket in place while I install the part. Figure that if I'm going to put something on there it may as well be designed for the purpose.

Never had much luck using the schmoo in place of a gasket, though. Maybe I was just impatient and didn't want to wait for it to cure enough.

 

[NJ Farmer]

The problem with RTV gasket makers (at least my opinion) is you need a jack hammer to remove the item if it needs to be removed in the future. You can damage the cover or other areas just trying to remove it.

Personally I leave RTV for sealing my shower doors or house siding. Aviation Permatex or even Dow Corning 4 (silicone) on gaskets that don’t have oil or grease really is a mechanic’s choice when you need possible to go back and remove something with ease.

DC-4 works great on intake gaskets or orings because you won’t have to spend anytime scraping off the gasket that gets bonded to the metal. It will come off in one piece. DC-4 is also great on o-rings because it allows the o-ring not to get glued during temperature changes and is allowed to flex if needed.

Anyway is personal preference and I’ve been twisting wrenches on cars, trucks, tractors and airplanes for over 30 years so I am still learning every day.

NJ Farmer