It's the Guillotine! Valve Replacement Questions

[catnip]

I won't address your suction valve questions, but will the backwash valve idea. I had the same problem with a leaky spider gasket spilling water to the backwash. The pool service guy put a ball valve on the backwash exit to prevent the water leakage. Bad idea! Pressure built up in the backwash line and caused the little rubber check valve in the site glass to continuously leak due to the pressure in the backwash line. I strongly recommend replacing the spider gasket in the multiport valve. A handy pool store did if for me for around $30, considerably less than the cost of replacing the multiport valve. And the multiport valve now works much more smoothly without any leaks.

[simsjim]

I didnt think of the 'upstream' impact of a valve on the backwash line. That's great advice Chuck...Thanks!