Toilets, Sinks, Showers, Tubs and Disposals - Diverter valve problem

I installed new valve stems in an old Price-Pfister tub/shower valve. Shutoff valves work fine, but the shower diverter lets lots of water thru the tub spout regardless of position. In fact, the best flow thru shower is with the diverter full-CCW --which doesn't seem logical. (You'd think turning diverter CW would close the tub spout passage and force water to showerhead.)

Valve seat looks to be in good shape, and washer is smooth/new. Only odd thing I see is that the old valve has a nylon washer *behind* the valve face --that is, between the valve face and the "diverter bonnet"--that the new one doesn't have. This would let you back-seat the valve against the bonnet on full-CCW --though I can't see a need to do this.

PF's exploded-parts drawing didn't help.

Thanks for any ideas/suggestions!

Diverters work CCW-shower and CW tub, and they should go lock to lock. Anything in between is insufficient movement of the washer and stem.

I finally got it to stop leaking thru the tub spout by using a standard hose washer between the valve face and the diverter bonnet. Still don't understand why that worked, because both metal surfaces were ground true and should have been sealing, but...it works. May just be blind luck. In any case, thanks for the explanation, Chandler.