Leaking Magnum Force Pool Pump

#1
I had a small leak in my Jacuzzi Magnum Force pool pump. I replaced the shaft seal, eye seal at all gaskets. I also had to replace the impeller as the shaft was cracked. Now the pump will not suction any water into the pump reservoir. What could be causing this?
 

setsailsoon

LifeTime Supporter
Oct 25, 2015
607
Stuart/FL
#3
As Allen indicated add water to the suction strainer bowl. If this doesn't work it's almost certainly a gasket leak in the cover or one of the o-rings in the pump assembly. Check to be sure they are all clean and there's no crud in the groove. Lube them with a very small amount of silicone pool lube, take care not to stretch the o-ring. Unless you have an extraordinary lift or long run you should get at least a small flow into the pump almost immediately after you fill the bowl. And remember the pump is not designed to run dry for long periods of time. Water cools the seal assembly.

If you have an air leak and just can't find it try this. Hold a hose over each component so the water covers the potential leak sources. If you notice a change in the sound of the pump you've found a leak source.

I hope this helps.

Chris
 
#4
As Allen indicated add water to the suction strainer bowl. If this doesn't work it's almost certainly a gasket leak in the cover or one of the o-rings in the pump assembly. Check to be sure they are all clean and there's no crud in the groove. Lube them with a very small amount of silicone pool lube, take care not to stretch the o-ring. Unless you have an extraordinary lift or long run you should get at least a small flow into the pump almost immediately after you fill the bowl. And remember the pump is not designed to run dry for long periods of time. Water cools the seal assembly.

If you have an air leak and just can't find it try this. Hold a hose over each component so the water covers the potential leak sources. If you notice a change in the sound of the pump you've found a leak source.

I hope this helps.

Chris
Thanks for your input. I was able to get the pump to suction by shutting off the solar panels on the roof. But after replacing the gaskets, eye seal, shaft seal, and impeller, I'm still having a small leak at the bottom of the mounting nut. Could the problem stem from a bad seal housing or motor housing bracket. Both are probably 17 years old.
 

setsailsoon

LifeTime Supporter
Oct 25, 2015
607
Stuart/FL
#5
Could be but depends on exactly where the leak is. I don't know the exact location of the part since I don't know the pump model. Any part that is exposed to pump suction conditions have a vacuum when the pump is running and can leak in air. Discharge areas of the housing have positive pressure so the water will leak out and not cause your problem. My experience is the leaks can happen almost anywhere and with a pump that old the housings have taken their share of abuse. These hair line leaks can be difficult to locate. There are a lot of detective tricks. Water dribble works well and I've taped a paper towel on the suspected area and even used water detecting paint (sold at NAPA and used to check for water in the bottom of tanks at gas stations). Make sure you find the actual leak as you can spend a lot of money replacing parts that don't need replacing. The parts you're talking about are usually $50 or less so repair still makes sense so long as you can still find them.

Good luck, I hope this is helpful.

Chris