[Keith Jordan]

Fyi for any dealing with this.I had a
Little flow thru my shower.took valves out and they were full of junk.Cleaned and reassembled flow was better for a couple of minutes.took back apart cleaned again.Removed supply lines to valve ran into bucket until half full.Reassembled Improvement but still not happy.Few hours later water pump starts running with everything off.shower is running in the off position.take stop valves back out and they look good.start measuring id.One valve is .008 larger so I swap them from hot to cold.No change.I order 2 new valves and when they arrive measure them.Same deal one is .008 larger id.so I proceed to install every combination.large id in both sides,small id In both sides,small one side large in other ,then swap those still will not shut off.What would Richard do? ride a zebra or shoe a horse?Walk away and think without the anger.When I do that something pops in my brain.every time I remove the valve the small o ring below the screen comes out of the groove.I get my trusty camera on a stick and take a look.There is white hard stuff on the surface the o ring sits.I remove that very carefully with a pick and scotchbrite.Fixed.good luck