Sprinkler Valve Repair -Stuck On Again?

Hi Craig,

One of the valves of my irrigation system was stuck open, so I replaced it. The new valve worked for about 3 or four cycles, but its stuck open again. I am trying troubleshoot the problem. Could you give me an idea of what could the problem ?
Thanks for your help.

-Sohail

Hello Sohail, that's big PIA! You already did the repair once, now you've got to do it again.
On the positive side, I'm sure you can do it quicker the 2nd time around :)!

I do not have a lot of information to work with, but my guess is this:
At some point in the recent past, you had a mainline break. Somehow some dirt or rocks got into the mainline system, and this debris is still causing a problem.

My suggestion would be to dis-assemble the valve again. This time dig a sump "12' deep hole) next to the valve. With the valve dis-assembled, SLOWLY crack open the water source (water meter,backflow, or slowly open the gate valve on the pump).

What you are trying to do is SLOWLY flush out the debris from the mainline. The sump hole is where you can bail out the water as the mainline flushes. A hand bailing pump (available at boat supply stores) makes that part of the chore very easy.

after flushing the mainline, re-assemble the valve.
Hopefully this will work for you.