On my westerbeke 10-2, the raw water impeller housing has a thin paper gasket from the factory. Anyone ever use a tube of gasket maker to seal the impeller cover? The paper tends to leak
Paper raw water impeller gasket - quick Q
- Thread starter SV_IdleHour
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I usually make a new one from a crackers or cereal box. It doesn't leak. Have you taken a close look at the metal surfaces on which it rests? Are there any gouges?
Thanks! Appreciated. I heard something about the thickness having to be exactly correct somewhere, and didn't know the veracity.
I've sanded/polished both sides and the crust might have been the gasket LOL.
Could the lip seal be leaking? That is what happened to the water pump on my Hunter 386 Yanmar, which I then replaced the entire pump. You might find this thread helpful: Raw Water pump leak | SailNet Community
Be careful. Our Genset has an Oberdorfer sea water pump that uses a thin paper gasket as well. The thinness of the gasket is very important on our pump and likely yours. As long as the pump housing and cover surfaces are clean and clear of any old gasket material or gouges, it should not leak. Apply a thin film of non-petroleum jelly to both sides of the paper gasket and see whether that solves your leak problem.
On our pump the neoprene impeller vanes must protrude about 1/64" past the housing surface so that the impeller vanes press lightly against the cover in order to make a tight seal. This is important for the pump to self prime. That 1/64" is about the same thickness of the gasket. Any thicker and it will likely not prime.
On our pump the neoprene impeller vanes must protrude about 1/64" past the housing surface so that the impeller vanes press lightly against the cover in order to make a tight seal. This is important for the pump to self prime. That 1/64" is about the same thickness of the gasket. Any thicker and it will likely not prime.
You're welcome. Please let us know the outcome and whether the leak stops.
Same thing I've got on the raw water pump of a Yanmar. The paper gasket is like tissue paper and soaks up water and leaves salt deposits around the casing. Try rubbing the gasket with Super Lube or any other synthetic grease (no petroleum grease) and work it in for a minute or so. The grease add some degree of waterproofing and reduces (not eliminates) leakage.
The gasket thickness is critical or the pump loses capacity due to recirculation from the high pressure discharge back to low pressure suction.
If you can't find one, you can make one from thin paper bag material.
Just measured same. Factory gasket thickness on Johnson pumps is .006". Standard brown grocery bag is .006" too.
Or use a US $20 bill. These are .005" so that would work with a bit of gasket dressing - like Permatex #2 or Permatex #3 (Aviation.)
Charles
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Morning de-winterizing went great, got an impeller kit with a new gasket, no leaks. (Can check how the lift went in the PM in the "tabbing cracked" thread. Thanks everyone!
My boat has a Johnson pump and it never had a gasket. Instead it has an O-ring. When I buy a new impeller, it comes packaged with a couple of new O-rings.
The only bad part for me is the pump being located “backward” on the engine. I have to pull the thing to get at the cover. I figure as long as it has to come off, I may as well change the belt too.
Impossible. No true sailboat part costs $1
Surely you jest. Are you sure I couldn't just use a one dollar bill ?