Pentair Superflo 1.5

Having trouble holding  prime, seems to be a lot of air in the system. I have replaced all O-rings and seals on suction and pump side. I’m starting to think the pump may just be old and give out. My question is, how does one know when the pump is shot? It is pretty weathered looking and age is unknown, as I just bought the house in December.

The pump is usually ok unless the housing is cracked.

As far as the air in the system, there may be some other areas to check.

Make sure the water level in the pool as at least halfway up the skimmer door opening.

Pump lid O-rings are a habitual offender of air leaks. The O-ring can expand or deteriorate over time and allow air to enter the pump. You can try applying a silicone or Teflon lubricant to see if it helps, but often times it needs to be replaced.

Plumbing fittings will also draw air. A popular technician trick is to use burning incense. While the pump is running, wave the burning incense near suspected areas. The smoke will be drawn in, if there is a leak. Check the fitting on the pump intake, the couplings and elbows. Cut out and replace any fittings that have an air leak.

Valves can be inspected like the plumbing fittings. Diverter valves will usually have internal O-rings. These O-rings can easily be replaced to fix an air leak. Simple ball valves are not usually repairable and need to be replaced, if there is a leak.

Drain plugs are found on most pumps. These plugs are usually used to drain the pump when a pool is winterized. They should be tightened firmly into the pump. Inspect the drain plug and drain plug O-ring. Replace them if they look decrepit.

I’ll try the smoke test. However I have replaced all O-rings and seals already, accept for the janky valve. The pump will prime for 30 seconds to a minute then I’ll see a huge pocket of air come into the pot and it loses prime. I found out the pump is 4 years old. Been having trouble for a few weeks now, but I’ve been able to get it running and let it run for a few days until it would fill up with air and I’d have to start over. ???

Four years old is pretty young for a pump. I would check all the joints and the jandy/diverter valves for air leaks.

Smoke test confirms no air leaks. Maybe a cracked pipe in the ground somewhere between the skimmer to the pump. I’m going to pull the pump now and split it from the motor and see what the impeller looks like. If all checks out there I guess I’ll have to pressure test the pipes underground and see if I have a leak there.

Come back and let us know what you find. Good luck!

Impeller seems to be fine, no blockage, spins freely. Is it possible that the pump motor is just weak? Maybe from overheating? Having a hard time convincing myself that I have a leak underground

The motors don’t usually slow down. They run consistently until they stop running. However, if you can’t find an air leak, it’s worth a shot. What is the catalog or model number on the motor label?