The rubber part of raw water impeller detaching from its core (a metal cylinder)


Member I
We recently had a raw water pump impeller failure causing the engine (M25 Universal) to overheat. As it turned out it was the rubber part of the impeller that got somehow disconnected from its core (a medal cylinder). In other words, the connection between the two parts, which should have been solid, allowed for slippage between the two. (Not sure how the manufacturer secured the link between two parts to form one unit, glued?) The rubber part looked still like new so this must have been a mechanical failure and/or designer flaw. Not sure if the impeller was an aftermarket unit bought online. After inquiring with West Marine it appears that recently there have been similar reports of such a failure. Caveat emptor!


  • faulty raw water impeller.JPG
    faulty raw water impeller.JPG
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Christian Williams

E381 - Los Angeles
Senior Moderator
Blogs Author
Brand unknown, right? Well, I suppose weird failures like that are why we carry a spare or two.

Good catch on the overheating. There are boat owners who don't even realize they have a temperature gauge, much less monitor it.

G Kiba

Member III
Had the same happen last month. A brand new impeller from Catalina Direct with not more than 20 minutes on it. I sent it and the spare I bought from them back.