Greetings hrd2fnd welcome to the Forum.
You tried powering up that Valve with an independent source ?
Like take a old Extension Cord and cut the receptacle end off of it, and put the wires directly on the Valve electrical connectors.
Plug it in briefly, and see if you get a flow.
Also, you might do an Ohms/resistance reading on the winding of the Valve Solenoid, just to see if it was open ?
Just sounds to me like the Valve isn't responding to power.
Another thing is that you can wire a larger Light Bulb (100 watts or so) up to the wires that power the Valve, and see if the Timer will light the Bulb up FULLY. If not, you may have a contact problem in the Timer.
Try that.
Have a good Day !
S.W.