Pentair Valve Gasket--any tips?

[Durk]

I have the Pentair version of the Jandy Never-lube valves on my 2004 A&S pool. The diverter valve between the main drain and the skimmers that feeds the pump intake has developed a slow drip (when pump is off) and air leak (when pump is on.) The drip is coming from the joint between the top of the valve and the valve body. Bearing down on the screws is no help. There does not appear to be any crack in the valve body or cover.

Has anyone had or seen this problem? Is the fix a simple gasket swap? Unfortunately, I'll have to drop the pool level by maybe two feet to service this thing, and I'd like to have all my ducks in a row. If I have to swap it, I'd lose three valves and a union and it would require cutting back three 2" risers almost to the ground. I am getting a fair amount of air and pH has been rising far more than I am used to (3 gallons MA so far, more than I would use in a normal season.)

Thanks. I searched but got nothing relevant. This is my first thread start. I really can't understand why this thing would leak if there is no crack and the screws are tight.

 

[Mr. Ed]

There is a gasket on that cap that may need servicing (clean and lubricate) or replacing if it is cracked/stretched.

 

[Bama Rambler]

Since you're going to have to lower the water level and you don't want to do that any more than is absolutely necessary. I suggest installing a complete gasket kit for the valve. Be sure while you have it apart that you closely inspect for any cracks or damage. I'd also probably check around with some local pool stores and see if they have a replacement valve just in case it turns out you have to replace it once you tear into it.

Post a pic of the plumbing where the valve is and maybe someone here can suggest a way to replace it without having to destroy the surrounding piping if it comes to that.