Hi, I absent-mindedly forgot to rinse after a long backwash and, when I returned the valve to filter, I got a lot of sand in my pool. Also, the six way valve got stuck & I can't budge it at all. I tried to unscrew the top from it so I can do a thorough cleaning but I can't separate the top from the lower piece of the valve part. My camera is not working at the moment but, if necessary, I can take a picture tomorrow. Does anybody know the problem I"m having without a picture? If so, any suggestion? My neighbor suggested wd40 or another lubricant but I'm reluctant to spray much of that on the filter. Thanks.