Rodger,
Anti-seize compound, as others have stated is the solution. A hot air gun is
dangerous to the shaft seal, but then, so is a misused torch. The key to
removing the impeller is to heat the impeller, but not the shaft. This will
be easier to do with a small tipped acetylene welding torch used VERY
carefully. Do not heat until you are prepared to pull immediately, otherwise
the shaft will heat through heat soak.
Steve
"Roger Long" wrote in message
...
I tried to replace the damage raw water pump impeller on my Yanmar 2QM20
today and found it frozen on the shaft. It's the slide on keyway type
without a set screw and the bronze impeller hub seems to have frozen to the
stainless steel shaft.

I cut the rubber away so I could get vice grips on it but it is really
stuck on there. It was only put in new last spring. I'm going to let the
boatyard replace it but this is something I really would not want to be
dealing with anchored on some lee shore with a damaged rig. I'm going to
buy a gear puller if I can find one that fits but cutting the rubber away
would be no picnic in rough conditions either.

Is there anything that can be put on the shaft that will prevent this? Or,
should I remove the impeller and grease the whole thing every month or so?

--

Roger Long