I have a Volvo Penta MD21 where I had problems with the sea water pump
leaking water into the engine. A new, expensive pump lasted 240 engine hours
before starting to leak again!
After cleaning the heat exchanger, which significantly improved the water
flow, it seems that the pump is now functioning much better, have now 1000
engine hours and still no leak...fingers crossed.
Martin

Martin's temporary email account at Bell Canada

"Steve" skrev i meddelandet
...
In my experience with Johnson or Jabsco pumps, there is a weep hole that
should tell you if the seal is leaking and this weep hole is before the
water can get to the bearing or into the engine.

Always make sure the weep hole is on the bottom of the pump housing and
never plug the weep hole.

IRC there should be two seals, one with the lip pointing in and one
pointing out. If you only have one seal, then the lip should be pointing
towards the impellor.


--
My experience and opinion, FWIW
--
Steve
s/v Good Intentions


"Garland Gray II" wrote in message
news:yEeBf.14823$CV.3437@dukeread03...
I'm interested in others' experiences in pump rebuilds.

I just rebuilt (seal and impeller) a Johnson pump that had started to
leak . "Just in case", I bought a new pump as a spare (Mack Boring said
they didn't fool with repair if one leaked, only impeller replacement),
and sure enough, before I installed the pump, I decided to replace it
because it didn't rotate smoothly.

Now a couple of months later I got around to taking the old apart to
figure what the problem. The bearing is frozen, presumably from seawater
leaking on it.

Since I've not had an impeller to fail, I'm thinking it is more important
to replace the seal every couple of years, and while at it, go on and
replace the impeller. Got to protect that bearing.

What do you think ?