What Sealant Do You Use on New Water Pump Gasket?

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Preparing to replace the water pump in my '99 3800 Series II NA with 152K in an Olds Intrigue. Am I silly considering buying a Felpro gasket for $5 when a thin paper gasket comes w/ the water pump (Autozone Duralast)? What sealant do you folks use on the gasket? Both sides?
 
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I have used one of the ultra silicone Permatex or equivalent on both sides of the thin paper gasket, but it is a very thin coating-just enough to say there is some on there. Never have any leaks doing this. It sort of permeates the paper and makes it a better gasket that the coolant will not channel through over time. The Permatex non-hardening would do the same thing. I am a little wary of these new coolants since Dexcool showed up on the scene and had a way of leaking more easily than the conventional green coolants, in my experience.
 
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Permatex makes a "Water Pump / Thermostat" gasket maker that sets up pretty quickly and bonds a bit harder than silicone, never had a leak when using it. It is gray in color.
 
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#2 Permatex will seal it , alright. But it is rather tough to remove in the future. #2 is great for any bolts that go into water/coolant and need to be sealed,BTW. A thin coat of good silicone RTV is what I'd use for a gasket. Let it cure a few minutes before assembly, and a few hours at least in warm weather before filling the system.
 
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I've also used the Permatex #2 non-hardening for the water pump, thermostat gaskets, and the water pump bolts as mechtech2 says. I find I have no problem removing the coated gasket later on as it tends to keep the gasket intact and lifts off fairly easily.
 
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 Originally Posted By: mechtech2
#2 Permatex will seal it , alright. But it is rather tough to remove in the future. #2 is great for any bolts that go into water/coolant and need to be sealed,BTW. A thin coat of good silicone RTV is what I'd use for a gasket. Let it cure a few minutes before assembly, and a few hours at least in warm weather before filling the system.
+1 \:\! Don't forget your engine is assembled at a factory and cures for quite a while before being filled with Coolant so this is really great advice!
 
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 Originally Posted By: Chris142
Nothing. When the paper gasket gets wet it will expand some and form a tight seal.
Just like the G.M. intake manifold gaskets I always used ultra blue Permatex.
 
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Dad always used the Permatex Red spray. I can't remember the exact name (Hi-tack, something or other), but it worked great, for T-Stats and water pumps. He made sure everything was clean and dry. Then he sprayed the mating engine surface, the back of the pump and both sides of the gasket. Never a leak. AD
 
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 Originally Posted By: Chris142
Nothing. When the paper gasket gets wet it will expand some and form a tight seal.
[Lumbergh voice]Um, yeah, I'm going to have to disagree with you.[/Lumbergh voice] If it's a good quality paper gasket on a nice, new flat surface- then I'd agree with you. But when we're talking about thin/cheap aftermarket paper gaskets being used on old, pitted, less-than-perfect sealing surfaces... you'll likely have problems if you just put the gasket on dry. IMO, it isn't that critical just what type of sealant you use- as long as you put SOMETHING on the gasket to fill in the imperfections (coolant is thin and tends to look for a way out). I've used silicon, anaerobic sealant (loctite 504, 555 or the like), aerosol hi-tack, aerosol copper hi-tack, 3M weatherstripping adhesive, permatex #2, aircraft gasket dressing, spray paint, Indian Head gasket shellac, hylomar... probably a few others. All with good results. Of all those, I probably like aerosol hi-tack the best. It sticks the gasket in place nicely, helps it seal, and is easy to apply. But it tends to make an overspray mess. None of my concern- but some people care what an engine looks like.
 
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 Originally Posted By: Solo2driver
Permatex makes a "Water Pump / Thermostat" gasket maker that sets up pretty quickly and bonds a bit harder than silicone, never had a leak when using it. It is gray in color.
This is my recommendation as well...
 
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 Originally Posted By: ADFD1
Dad always used the Permatex Red spray. AD
I love that stuff. Sometimes I'll use it just to hold a gasket in place during assembly.
 
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Anything that makes a paper gasket stick is a no go for me. I'll use silicon for reusable gaskets ..or for the gasket itself. It peels off easy enough on the 2nd or 3rd round. If it's just paper ..like a thermostat, then it's just never-seized on both sides. A very common practice in industrial settings ..steam ..whatever. I hate having to clean up a surface, especially if it's a recurring replacement item (like a thermostat). I see that they make thermostat gaskets with a sticky side so you can attach it to the housing to aid in putting it together (given the odd places that they may be in). This costs me time.
 
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It's the same as their Import Grey silicone. I used Ultra Black on a Toyota with no issue, while I old good old gasket shellac on a 1984 Mercedes 380SL water pump gasket.
 
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 Originally Posted By: XS650
 Originally Posted By: ADFD1
Dad always used the Permatex Red spray. AD
I love that stuff. Sometimes I'll use it just to hold a gasket in place during assembly.
I've tried just about everything over the years and found Hi-Tack (the Permatex Red), to be about the best. The over spray sucks, but if you wipe up the over spray with brake clean it cleans up pretty good. I never had leaks after using that, other products have let me down. JMO
 
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