I have a Hayward GM series sand filter 1.2 effective filter area. I notice when I remove the clamp and pull the entire valve body off the tub, the "Main pipe" that goes down into the sand fits loosely onto the valve. I stirred up the sand and reassembled the filter. Upon starting the pump there was a brief discharge of sand. Is it possible that some water can be bypassing the sand and going between the pipe and valve body (where the pipe connects into the body). I noticed the pipe is abrased, where it connects into the valve body. Is there some dye or something I can place into the skimmer to test?
Possible Internal Sand filter leak
- Thread starter steppinthrax
- Start date
I can not help you with your sand filter problems but I know someone else can. Lets 
the thread and see if we can get your question answered. 
the thread and see if we can get your question answered. 
There is usually an o-ring in the valve body that seals agains that pipe. Sand shouldn't be getting up that high in normal operation, so that pipe doesn't need a perfect seal.