water escaping thru backwash line when pump is on

Sep 11, 2009
I have seen variations of my question on here, but I need help with fix.
I have a Hayward Pro-Grid DE filter. When the pump is running, I can walk to the front yard and hear the water escaping through the backwash line.
I have been told that I need to replace the "bottom O-ring" and that it is an easy fix.
When I look at the diagram of my filter online, I see an awful lot of O rings and I am not sure which one is the "bottom O-ring".

Is there somewhere I can go for detailed instructions for taking apart and putting back together the section that needs the replacement o-ring?

Will Leslie's carry this replacement part in the Dallas metro?

Thank you!


TFP Expert
LifeTime Supporter
Mar 29, 2007
Coastalish 'down easter'
Welcome to TFP!!

Leslies should carry the SP 715-D spider gasket you need :cool: (if you pipes are 1 1/2" it's a SP 710 - X-D)

One of the spokes on your 'wagon wheel' gasket (A/K/A spider gasket) is warped most probably.

Procure the recommended gasket and we'll talk you through what to do with it :)
Sep 11, 2009

I have the two-position 2" slide valve if that makes a difference. Not the Vari-Flo or Selecta-Flo.

I pull the valve up for backwash and down for normal filtration.

Don't know how much that info matters except it seems this is where the blown part must reside.

Going to Leslie's now.
Sep 11, 2009
That helps I believe. Leslie's sold me a Hayward SP410 kit. It contains 4 O-rings. One is very tiny, the size of my pinky finger around. The other three are a little less than a soda can size and vary slightly in thickness.

Leslie's thought there might be 2 screws on the top of my slide valve assembly, but I am not seeing any. Should I be able to twist the base that the push/pull handle comes out from? It has ridges that might indicate this is the method.

Once I get this valve assembly open, I imagine it may be obvious where the rings should go. And I know I should lube the rings. Any other advice?