gear type water pumps

[chippie]

Does anybody have any knowledge of gear type raw water pumps? I have seen several of these ,all on marinzations and not quite as compact as impeller versions but seemingly very reliable . I wonder why they are not used more frequently as it would remove the dangers of impeller failure. They have all been remote type fittings ie. driven by a belt similar to an alternator.

 

[dickh]

I'm sure they were fitted to the Albin range of petrol engines - I had the small 7hp one in a Halcyon 23 and I didn't have any trouble with it at all - in fact never even took the cover off to have a look at it in 3 years. The Albin one was permanent in that it was directly driven from the engine and not belt driven - If I remember correctly you had to make sure a little hole was clear to make sure any water leaks dripped into the bilges and not back into the engine.

dickh
I'd rather be sailing...

 

[ccscott49]

I had a boat, with perkins S6M engines, these had direct drive bronze gear raw water pumps, the engines were raw water cooled, one of the pumps had already been replaced with a jabsco, I replaced the other with a jabsco, because it was getting worn and needed some revs to get it primed, I wish I'd never done it, they were reliable even if they were a little inefficient in the first few moments. I was young and new to boating, but I was an engineer and should have known better!