Getting ready to replace my radiator and do a general cooling system overhaul (sans water pump). Got a new water outlet, and as the title says, I'm not sure what if any gasket sealer to use on the gasket.
Water outlet gasket, use sealer or no?
- Thread starter twistedlv
- Start date
Thermostat housing. It has a gasket, but there is always some debate as to what kind of sealer may or may not be necessary. It's one of those thick paper style gaskets.
Paper gaskets work fine/great, that's what the factory uses. I cut an emergency thermostat housing gasket out of a cardboard MRE box on the trail and it worked perfectly fine, no leaks. I didn't bother replacing it for several months
I try to never put sealant on the engine side of a paper gasket. Makes it harder to clean off later, but I generally use a very light coat of permatex on the (in this case) housing side.
Dont put anything on the gasket. Just make sure the surface of the block is 100% clean. The smallest piece of debris will cause it to leak. I went at mine for well over an hour carefully with a razor blade and wire brush.
The threads on my thermostat housing pass into the coolant passages, if I don't seal the threads it leaks. I guess some people don't have this problem but I have forgotten a few times and had leaks. The factory service manual specifically says "the gasket is installed dry" but the factory gasket has a silicone bead facing the water pump or housing. If your replacement gasket doesn't have the bead I don't think it could hurt to follow the advice given by @Goatman.
