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post #7 of Old 06-05-2008
JohnRPollard's Avatar
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That is not a very old pump, at 10 years of age. We have the same engine, and ours is the original pump at 18 years. Engine hours are more of the issue.

I can't say for sure where it's leaking from. Could be the gasket has a bad seal. The shaft seal is the other likely culprit.

On a previous boat with a 2GM20F (exact same raw water pump), I had a drip leak from the shaft seal. This leak developped at the beginning of the season, after I had de-winterized the boat. It was my first year of boat ownership, and when I had winterized the boat at the end of the previous season, I had neglected to loosen the raw water pump belt. This caused the shaft to have uneven pressure on it for several months, resulting in the seal becoming slightly off-round/misshapen.

When I detected the leak, I had the same thought as you: Buy a new pump, and/or re-build the old one as a spare (re-build kits ARE available). But an experienced mechanic gave me some good advice: He said to use the engine as much as possible, and see how much the pump was dripping after a month or so. He was right, it turned out that by operating the pump, the seal re-seated/shaped itself and the leak dissapeared in a few weeks.

You might try this too, especially if the boat had been sitting for a while with a tight belt. Just a suggestion, Good luck!

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Pacific Seacraft Crealock 31 #62


Last edited by JohnRPollard; 06-05-2008 at 11:58 AM.
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