Backwash valve leaking out waste

[Debigold]

Hello Everyone,
Our hayward push pull backwash slide valve was slightly leaking at the elbow of the waste pipe. Not enough to come all the way to the end, but just enough to drip slightly at 1st elbow. We have replaced all o rings and still have the issue. Now what? I appreciate any help
Thanks

 

[Texas Splash]

Did you simply replace the o-rings, or did you do a rebuilt kit? Used some silicone lube too? You may need to replace the entire piston assembly, much like the one you see HERE.

Of course you have the option pf investing a little more and going with a multiport valve.