The saga is over
The saga is over but not without some additional twists and turns.
I installed the new Attwood Sahara 500 pump which is the same case as the 750. Output was a bit anemic but I didn't think that was a problem since I'm usually pumping less than a gallon.
First night of a cruise two days later, I heard a sound I first thought was a boat propeller. When it didn't stop, I looked in the bilge and found it full of water with the pump running continuously and nothing coming out the transom. Float switch working perfectly as verified by using the hand pump that draws from the same sump. Disconnected and blew through the discharge line: clear.
I spend the whole cruise hand pumping the grey water. No big deal except on the rainy day since the pump is in the cockpit.
When I got home, I removed and hooked up the pump with clear plastic hose and verified that it won't lift as high as from the keel sump to the top of the loop in my bilge system. Evidently, it would right out of the box but not after a couple days in the bilge environment. I took the impeller guard off the pump to be sure it was clean and clear.
Hamilton, with their usual great service, took the Attwood back even covered with slime and with my screws epoxied to the float. They don't carry the 750 so I ordered one on the Internet. I put it in this morning and everything works just like it always did.
I now suspect that there was nothing different about the model 500 I bought. Since it was operating right at the limit of its static lift, a marginal float switch design may have only shown a problem in that situation. They insist service history has been good.
If I were doing it again or, if I ever redo my bilge, I'll probably go to a manual diaphragm pump in the galley for the gray water. Being able to just plug another Attwood into the already mounted strainer was essential not to turn this into a major rebuilding project involving all my pumps, however. For now, everything is as has worked very well for three years.
The saga is over but not without some additional twists and turns.
I installed the new Attwood Sahara 500 pump which is the same case as the 750. Output was a bit anemic but I didn't think that was a problem since I'm usually pumping less than a gallon.
First night of a cruise two days later, I heard a sound I first thought was a boat propeller. When it didn't stop, I looked in the bilge and found it full of water with the pump running continuously and nothing coming out the transom. Float switch working perfectly as verified by using the hand pump that draws from the same sump. Disconnected and blew through the discharge line: clear.
I spend the whole cruise hand pumping the grey water. No big deal except on the rainy day since the pump is in the cockpit.
When I got home, I removed and hooked up the pump with clear plastic hose and verified that it won't lift as high as from the keel sump to the top of the loop in my bilge system. Evidently, it would right out of the box but not after a couple days in the bilge environment. I took the impeller guard off the pump to be sure it was clean and clear.
Hamilton, with their usual great service, took the Attwood back even covered with slime and with my screws epoxied to the float. They don't carry the 750 so I ordered one on the Internet. I put it in this morning and everything works just like it always did.
I now suspect that there was nothing different about the model 500 I bought. Since it was operating right at the limit of its static lift, a marginal float switch design may have only shown a problem in that situation. They insist service history has been good.
If I were doing it again or, if I ever redo my bilge, I'll probably go to a manual diaphragm pump in the galley for the gray water. Being able to just plug another Attwood into the already mounted strainer was essential not to turn this into a major rebuilding project involving all my pumps, however. For now, everything is as has worked very well for three years.
