Whitby 42 Brewer Sail Boats

Has anyone had to replace the entire raw water pump? I have the newer Johnson pump, that is supposedly self priming. It stopped suching in the midst of winterizing, and I've replaced the impellor, checked all hoses, removed the strainer and flow alarm from the intake line, blown air through the heat exchanges to see that there is no blockage......and still no suction.

One our trip up the river to be hauled out, we ran the engine for several hours with no overheating.

Since I carry a spare pump, that will be my next step. If anyone has done this, I'd be interested in what's involved.

thanks,
Roy B.
S/V Serenade

Did you check the backing plate behind the inpeller? When mine wouldn't pump I checked the imp[eller it was good, so we looked further and found the backing plate had worn through and created a leak path between in and out.

Dan

Your suggestion turned out to be correct, although I really couldn't tell until I removed the old pump and got it on the bench. There was corrosion and wear on the back plate and along the edge of the compressionfoot. There was also some wear on the cover plate. Now I am wondering if I can obtain a new pump chamber without having to purchase the entire pump fitting. That part seems to be fine.

Thanks for you help.
Roy Belcher