Sta-Rite System 3 Filter Body Leaks

[Dmooney]

After 20 years in service my Sta-Rite System 3 DE filter is leaking where the top and bottom sections of the body come together.
After cleaning and recharging the DE the filter would sometimes drip a little bit for a few hours and then would stop dripping (I presume that DE filled in the gap(s) where the water would leak. Unfortunately, after several years the leak was much worse and didn't abate. I then purchased a replacement O-ring, thinking that would solve my problem. I believe it did, at least until my most recent previous cleaning. The leak returned, worse than ever before. I have an automatic pool cover so my water evaporation loss is minimal, but now the water level drops much faster than ever before (because of the filter leak).

I just now finished cleaning the groove in the lower filter body and the corresponding sealing area on the upper body. The O-ring appears to still be in good condition. I applied a generous amount of Pool and Spa Lube and Sealant to both areas and reassembled everything, tightening the clamp knobs about as much as I could with my hands. STILL leaking, but in just one location now. I have not tried cleaning and lubricating the clamps to allow them to slide tighter more easily, perhaps I'll try that tomorrow.

Any suggestions anyone??

 

[ajw22]

Let's see if @1poolman1 has some pro tips to share.

 

[1poolman1]

After 20 years in service my Sta-Rite System 3 DE filter is leaking where the top and bottom sections of the body come together.
After cleaning and recharging the DE the filter would sometimes drip a little bit for a few hours and then would stop dripping (I presume that DE filled in the gap(s) where the water would leak. Unfortunately, after several years the leak was much worse and didn't abate. I then purchased a replacement O-ring, thinking that would solve my problem. I believe it did, at least until my most recent previous cleaning. The leak returned, worse than ever before. I have an automatic pool cover so my water evaporation loss is minimal, but now the water level drops much faster than ever before (because of the filter leak).

I just now finished cleaning the groove in the lower filter body and the corresponding sealing area on the upper body. The O-ring appears to still be in good condition. I applied a generous amount of Pool and Spa Lube and Sealant to both areas and reassembled everything, tightening the clamp knobs about as much as I could with my hands. STILL leaking, but in just one location now. I have not tried cleaning and lubricating the clamps to allow them to slide tighter more easily, perhaps I'll try that tomorrow.

Any suggestions anyone??

Did you get a new OEM tank O ring or generic? The generics, though much less expensive, tend to leak more than OEM. Also, I used to tighten the clamps then go back and, using a rubber mallet, tap them tighter and tighten the knobs again.

 

[Dmooney]

Thanks 1poolman1!
I looked back at my order history and I did order the more expensive Pentair O-ring and not one of the cheaper generic replacements.
Good news however! Following suggestions I found in another similar, older, thread, after releasing the pressure I removed all eight clamps and cleaned them and the tank surfaces and sprayed them with a silicone lubricant and retightened them in the manual specified sequence. This reduced the leakage from one drop every 4 seconds to one every 10-11 seconds, but after running for a while (30 minutes?) the leak stopped completely. I had never thought to clean and lubricate those surfaces and it made a significant difference.

New question: two of my clamps have lost the snap ring that keeps the hand knobs attached to the clamps. This ring has no function in tightening the clamps, but does allow the knob to withdraw the clamp from the tank when loosening it. Not a huge problem, but just a little annoyance. Any idea where to buy replacement snap rings? I tried using an e-clip, but it wasn't stiff enough to handle the forces. The clamps run over $100 each, which is too much to pay for what is probably a $0.50 snap ring.

 

[Newdude]

Take it to a hardware store. The guy behind the counter will open a few drawers on the fastener aisle until he finds the right one. It will save you an hour of hunting yourself.