AC Gasket replacement

[Sneakinup]

I know my AC gasket is shot, as I have experienced some leaks from that area. It is a Duo-Therm AC that has the 4 bolts inside that sandwich the AC to the roof. My question is...

What type of gasket is generally used between the AC and roof?

My SOB had a factory made replacement gasket. I have 1" diameter small cell foam that is used in commercial glass applications. I'm wondering if I contact cemented that down, and then tightened the AC down, if that would work.

Your thoughts, opinions, and of course "expertise" are welcomed!

[thenewkid64]

It is normally a single 2 inch continuous piece of closed cell foam. I would think that it would be available from CW at a minimal cost and that way you would be assured that the leak is fixed.

Now for the silly questions:

Have you removed the inside air box and verified that the installer of the new unit braced between the skins toward the rear or front. You coach, if equipped, would have had an Armstrong AC. It was lighter and was attached to the exterior sheet much differently that the newer kind. Upon replacement they should have placed a brace (normally wood) between the inner and outer skins to help support the AC. If hey did not do this it could be the cause of the leak.

I would go with a factory seal if I was replacing it as a home grown one may be prone to leak as well.

[Sneakinup]

I haven't yet removed the inner plate. I didn't want to do it until I had all the necessary components to finish the job.

But now that you mention it, I did notice that behind the ac on the roof, the aluminum has a bow to it. Not a dent, but it looked as if it was not supported underneath. I'll bet when I pull the inside plate, it isn't braced. I was wondering about water accumulating on the roof behind the ac and seeping in at that point.

Hmmmm. The fun things you find out!

Thanks for the suggestion. I will check that out and repair it before I put down a new gasket. You are right, I'd be best to just pick up the correct one and not fool with it.

Thanks again!

[Chas]

I would pull the inner or exterior shroud and see how the roof skins looks in comparison to the areas where there is no a/c.

Like Newkid says, if it wasn't braced properly you will continue to have problems even with a new gasket. The opening is quite flimsy without the proper bracing in place and was originally designed for the Armstrong units which mount quite differently.

Chas