I have a sweet-running Betamarina 25 installed in mid 2018. Only about 50 hours on it so far.
is there a recommended number of hours (or years) when he raw water pump impeller should be replaced? (On my former diesel I would replace the rubber impeller every other year, just as a precaution. I never had one lose a blade in over 20 years.
I believe in preventative maintenance, but also hate to arbitrarily spend money if there really is no need to do so.
Thanks much!
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40 years of racing, cruising, and deliveries. Enjoying our Ericson-built 1988 Olson 34, #8, since 1994.
There is no fixed rule here. It all depends on circumstances. You may be just fine with your limited use changing it every other year but if you pick up something that blocks the intake for a short while, this could destroy the impeller quickley by causing it to run too hot.
If you lay the boat up over winter I suggest that you remove the impeller and coat it with glycerine (or vaseline) and keep it in a ziplock bag to avoid the blades taking a set over winter. Just remember to refit it and then open the intake valve before starting the engine at the beginning of the season. I also recommend that you keep a spare on the boat for "in case".