I figured it out. I too thought spider gasket since that seemed to be the consensus on various forums and topics. When I disassembled it, the spider gasket looked fine.

So next thing I assumed maybe a broken lateral since I found sand in the discharge sock that had attached. So began removing sand.

Got to the bottom and the big white plastic tube was broken off right at the joint to the laterals. Off to the pool supply store for a new lateral assembly plus new sand.

All put back together running. I'm still not happy yet with the way it rinses as I don't see the swirl in the little jar but maybe it's doing it's thing. It's not leaking anymore so hopefully that's the end of it. Now on to the green.....

Quote Originally Posted by PoolDoc View Post
Usually, when a multiport leaks via the backwash discharge, it means that there's a problem with the spider gasket. I don't know why that would be the case on a new valve, but it's still the first thing to check.

Unscrew the SS bolts holding the lid in place. Loose them all gradually, and do not remove ANY bolt/nut pair, till they are ALL loose. The lid is spring loaded, and you'll crack the lid if you remove most of the bolts, leaving one in place. Inspect the gasket for problems, dirt, sand, etc. If you find nothing re-install and try again. Sometimes, the mysterious repair god fixes things magically when you take it apart and then reassemble it.

If not, come back and we'll go a step further.