gasket dressings

jdrotert · Nov 5, 2001

I've been meaning to ask this question to a forum for some time now to get an opinion. What are the pros and cons of using a gasket dressing? I'm talking about paper or cork gaskets here. I will be replacing a water pump on a Ford pickup this week. The pump seals are not leaking, but the paper gasket has failed on the lower side of the pump. I have used 3M westherstrip adhesive before, and it seems to work OK. I've seen aerosol spray versions from Permatex too. I used to work on race cars and the engine builder showed me a tip one night. When replacing a valve cover gasket, he spread 3M weatherstrip adhesive on the gasket and on the valve cover. He waited for both to dry, then stuck them together. This adhesive was like rubber cement. I don't guess it does much for sealing, but I've always done it since.

CVHoss · Nov 5, 2001

John,
My son and I have built a fair number of high performance engines and as a sealant for paper or cork gaskets, we use

. You can read about it here. Have not had a gasket failure using this stuff. Nasty, sticky, don't want to spill it, but it works great.

Hoss

cowboydoc · Nov 5, 2001

I use the same stuff except in the tubes and not the industrial size.

cp1969 · Nov 5, 2001

If everything is clean and flat, theoretically you shouldn't need any sealer. Most of the time, the only thing gasket sealer does it to make removal more difficult at a later date. Instead of coming off in one or two large chunks, leaving a clean surface behind, you get to scrape and wire brush the heck out of things to get a clean surface from which to start.

The trick of using weatherstrip adhesive on valve covers is not so much for sealant as it is to keep the gasket in position while it's being tightened down. Some valve covers let their gaskets squirm a bit.

Bird · Nov 5, 2001

Just depends on which gasket and where it is. On a lot of gaskets, I've just applied a little grease to hold it in place while I tightened the bolts (makes it easy to remove if I ever have to change it again), but like Hoss and Cowboydoc, I've used a lot of the Permatex also (in the tubes).

scruffy · Nov 5, 2001

Coppercoat for head gasquets, ... what the heck is the tube of blue latex (?) gasquet sealer for water/gas type gasquets?
Another senior moment there.

kubmech · Nov 5, 2001

Personal opinion only....

If it's a paper gasket I generally like to spread a thin coating of RTV by hand on both sides of the gasket (kind of messy on the fingers) It's just easy insurance in case there's a slight imperfection in the surfaces, and as long as it's a thin coatng it looks good when a slight bead surounds the sealing surface (warm fuzzy) /w3tcompact/icons/tongue.gif If it's a cork gasket I generally put them on dry (watch the torque or you'll squish it) nothing wrong with a little adhesive to keep it in place. The aviation cement previously mentioned is KILLER, and will most likely never leak. Just keep in mind if you ever have to access that area again it's a real bear to clean up and or get apart.
I generally use black or white permatex. Black dries pretty quick, short working time for getting things lined up etc. works good for stuff you want to get together and fill with fluid right away. White takes a lot longer to dry so you have more time for getting things set and in position. But you generally want to wait approx 12 hours before you add fluid. I'd probably use the black for the water pump gasket. If your wondering about the blue? It's about a medium dry time but personnaly ( and this is the only reason) I hate the way it looks /w3tcompact/icons/blush.gif Silly is'nt it.

Bird · Nov 5, 2001

And I guess most of us have had the fun of trying to scrape off old gasket material, and whatever sealer was used, with a putty knife; sometimes in very awkward places to reach, see, etc./w3tcompact/icons/frown.gif When my brother was running the tool truck, he sold lots of small angle die grinders along with some 3" diameter pads that looked something like the plastic pot scrubber pads used in the kitchen. Cleans all the old gasket and sealer off fast and easy and doesn't hurt the metal surface. There's been many a time I wished I'd have known something like that existed.

kubmech · Nov 5, 2001

Bird, those "roloc" pads you described are incredible!!!
Can't live without 'em now./w3tcompact/icons/smile.gif/w3tcompact/icons/smile.gif/w3tcompact/icons/smile.gif What a time saver................

Anonymous Poster · Nov 5, 2001

Bird, you have got to tell me the name of those little pads! I was in a shop where they had those and those are _the thing_ to take off old gasket crud! Of course nobody knew where the thing had come from. I went looking for them at a tool store and when I asked about them the guy looked at me like I had swallowed a bug.