Water Pump Problem

[John W]

I am stumped as to why my raw water pump is not pumping water. I just replaced the impeller, the other one was completely detroyed by a lack of water. I carefully cleaned out all the old pieces by removing the fittings. The pump just does not seem to produce any suction. I was thinking that the intake was plugged but I get plenty of water when I open the strainer cover. Does anybody have any thoughts? Does the pump need to be primed? What caused it to stop pumping water and detroy the impeller?

 

[Ken Juul]

RE: raw water

The pump should be self priming. If you are not getting water to the pump check the water line between the pump and the strainer for blockage. If it is clear, check the routing. Perhaps it has a "hump" that is causing an air lock. If it is clear and routing looks good, try filling it with water and try the pump again. To check for pumping I would disconnect the output hose rather than check the exhaust. You may have something up stream of the pump that is blocked causing a lack of flow.

 

[Paul]

pump

John,Is this on an Atomic 4? If so, I had the same problem after replacing my impeller. Mine would suck a little water but not enough to keep the engine from over heating. These pumps are self priming.I called Dan Moyer of Moyer Marine who is an Atomic 4 Wizard and he said he has seen this problem before with old pumps. He contacted the Manufacturer and their response was that the inner pump housing has wore beyond tolerances. The reason why the old impeller worked fine is because when it gets old it swells and this allows it to create the needed seal in the pump housing to pull water.The new impellers can't do this. His suggestion was to buy a new pump. I did and kept my old as a spare.Good LuckPaul

 

[John W]

M-18

Thanks for the advice. The pump is on a Universl M-18. I am still hoping I can get it working this weekend before spending $200+ on a new pump. I plan to replace the hoses and re-check the intake screen. I had a difficlt time several months ago getting a new impellar to fit on the shaft, sent to first one back, second one still too small. A little filing allowed it to fit, I can't help thinking this has something to do with my dilemma.