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Confusion about thermostat/water pump gaskets.

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Hi all.

I am confused.

I remember once on my old '97 Legacy 2.2 when this

guy changed the water pump because it was shot. He had

trouble getting the plastic fitting/bowl to seal to the water pump,

and had to order a new gasket from Subaru, which I believe was this

copper-type one made to crush when you tightened the bolts.

But now I am looking at this Aisin water pump which came with my

timing belt kit for my '95 Legacy 2.2, and it only has a black rubber

gasket. Am I remembering incorrectly back to my 97, is there a

difference between the two years, or should I get another gasket?

Thanks a lot.

Dan

Loctite 518 or permatex anearobic for the water pump to the block mating surface.

 

Rubber seal around the (new OEM) thermostat.

 

That's all there is to it.

 

GD

That black gasket is the good one. I have never seen one of those leak. Most of the aftermarkets come with a fiber gasket that I have seen fail. I wouldn't use this kind but if I had to, GD's recommendation on sealant is likely to be perfect for that.

The seal that wraps around the rim of the thermostat is the right one. The paper flat gasket that goes between the housing and the waterpump surface is the wrong one.

 

The rubber ring's tend to swell over time, I've had to put them in the freezer for an hour to get a used one to go back into it's groove in the waterpump.

That black gasket is the good one. I have never seen one of those leak. Most of the aftermarkets come with a fiber gasket that I have seen fail. I wouldn't use this kind but if I had to, GD's recommendation on sealant is likely to be perfect for that.

 

The rubber coated metal gasket is what you want to seal pump to block. The cardboard ones suck and often leak. Every WP I"ve seen leak had the cardboard gasket or RTV.

 

It almost sounds like you were asking about the thermostat purely rubber gasket because it goes between the pump and the plastic outlet piece.

I agree that the rubber coated metal gasket that the dealer uses and comes with the Aisin pumps is great. I use them if I have one.

 

For the NPW pumps I buy that come with the paper gasket I just use Anearobic flange sealant. Never had one leak. I use it for oil pumps, block halves, transmission cases, oil pans, etc.

 

I don't like RTV. It's messy and has a limited shelf life. Anearobic has an unlimited shelf life and is much friendlier to use. You don't need much. I've been using the same caulking gun tube for over two years.

 

GD

  • Author

thanks for the help.

as usual.

i don't for the life of me remember where i got that idea about

the crushed copper one. it wasn't the one that seals between the wp

and engine, it was the one that sits inside the bowl. Or maybe

the guy had to buy a new bowl because that has a gasket in the lip of it?

I know he had put it all together and i drove it and it was leaking from between the bowl and wp.

Thanks again.

Dan

I think the last thermostat o ring I got from the dealer was orange rubber. Perhaps you saw orange and assumed it was copper?

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