Bucket test

I have checked all possible air leaks including strainer (doesn't mean I didn't miss one) and think everything is tight. Disconnected hose from hull pickup and did bucket test there. Disconnected hose from tranny cooler and did bucket test there. Same results on time it took to empty bucket, so I'm thinking there is not an air leak between pickup and pump (again--I could be wrong). That's why I'm thinking it may be sucking air at the pump. The bearing seems to be good though.

I will recheck hoses tonight, perhaps I've got a crack in one--or the strainer. I think what Tim says makes sense...overheat at idle sounds like sucking air somewhere besides the pump.

Thanks guys. Merry Christmas!

If youre only overheating at idle, then you most likely have an air leak between the pick up and the pump. The increased RPM allows the increased water flow to overcome the small air leak. Check all hose ends for damage (cracks, etc) and tighten all clamps with a nut driver (not a screw driver). Also verify your strainer gasket is in good shape and that the bowl is installed very tight.

When a RWP is starting to pull air and fail, it will usually show up as an overheat at higher speeds/loads, not idle. Same goes for a blockage on the intake side.

I have several RWP's that leak externally a bit... but they must not be pulling air because they allow the engine to regulate proper temperature just fine under all conditions.

Thanks David. That's what I think too. Impeller is good...change it bi-yearly. The O ring in the pump has been an issue too...It never seems quite thick enough, but I've got several and they're all the same size. If you used permatex, which side of the brass plate would you put it on? pump side or housing/impeller side? I would think pump side, right?

I ordered a new rwp today. The bearing seems good, and it does suck water, but I am thinking it's just not enough--like you said. I figured it should empty that 5 gal bucket in 60 sec or less. I may try the permatex idea and if that seems to fix it I may send the pump back.

I appreciate your suggested sequence...I agree.

but i've had trouble with rwp--sometimes leaking. had to re-tap one bolt hole so I could tighten up...twice. I think it's sucking air on the intake side. However, I think replacing manifolds is good idea anyway....always a little too hot to touch in summer.

Like people are saying, you should see the level drop steadily, maybe 30 seconds to drain the bucket? Not sure of exact amount of time, but very fast.

What did you see when you ran the test?

I fill up a 5 gallon bucket before I start the boat, then I keep the hose on feeding the bucket. I can typically run it about 5 minutes before the bucket is empty - even with the hose on I cannot keep up with the water demand.

how fast should my RWP suck up a 5 gallon bucket full of water when I'm doing the bucket test on the pump?