Filter pressure fluctuates

[Bountyhunter5300]

Just opened the pool for the year and when i turn the pump on it primes good and reads about 10-12 psi on the filter gauge; it will continue running like that for between 1 and 5 minutes then all of a sudden the sound will change and it will drop to 8 psi for a few seconds then back to 10, then drop to 6psi and back to 10, then drop to 4 psi and back to 10 and will run at around 10 for a minute or so and repeat. You can also see air bubbles around the return jet. I checked the surface plumbing for any air leaks on the suction side with soap and water and also and water drips on the pressure side and there is nothing visible. I can't figure out what to check next or how to solve this. This is an inground pool with a hayward pump and hayward de filter, the pump is a year old, the filter about 5 years. Any ideas?

[Denniswiseman]

It seems that you have a suction side air leak
The only thought for the pressure fluctuation is that the higher pressure causes the suction leak and pressure drops off. When it drops off the suction side leak stops, it fills up and normal pressure for a while
Check the pump basket "O" ring and lubricate with silicon grease

[Bountyhunter5300]

Thank you for the response and that is a good thought, i used silicon grease around the pump basket, but sadly that didnt fix the problem. Even when i remove the pump lid you can tell it was under pressure because as i loosen it you can hear the suction release. I also tried cleaning the fingers and the filter itself. Still same is happening. I just don't know.

[Denniswiseman]

Can you run the pump at a slower speed

[Bountyhunter5300]

I cant, its a single speed pump.

[Denniswiseman]

Check if the pump basket fills with air, clears and then refills with air
What happens if you put the MPV to recirculate

[Denniswiseman]

Also check the water level at the skimmer and that the skimmer door isn't jammed up

[bigredwv]

Having this issue now. Were you able to resolve it?