SpudFiles

I am in the middle of making a 2" piston valve gb cannon. Everything looking good but when I put pressure in the cannon the sprinkler valve lets the air through with no resistence (almost as if it is open). The valve is modded for blowgun triggering, and yes the flow arrows are pointing in the direction of venting.

Wondering if maybe the valve is "normally open", or something like that? Any help would be appreciated!

Also I would attach some pics but I'd have to crop them so small to get them under 1mb that it would be pointless

Check all the sealing faces in the valve make sure they are clean. What are you using for a air source? Your typical sprinkler valve should seal at around 30 psi.

Checked immediately when it didn't work that everything was clean. Air source is a compressor @ 100psi.

I tried covering the opening with my hand in case it needed some back pressure to initiate but that didn't do anything.

Where are you filling from? Sprinkler valves typically need to be "shocked" into sealing.

Have you tried filling through the "trigger" blowgun?

Here's some pics.. Muchos thanks for the help

Some times the adapter will be scewed to far in and be touching the diaphram holding it open...

I tried to make sure it was only in enough to be just poking through the plastic, but if it is in fact too far I guess it's garbage now lol... I'll try putting air through the blowgun tonight like jsr suggested. That doesn't work it's looking like a ball valve trigger for now

Got it working!! For some reason it wasn't equalizing, so I put some pressure into the top half while putting pressure into it like normal. After that it seemed like the diaphragm had been "freed" and now it works great. Thanks again all!

Could it be that some epoxy seeped through when you were filling the solenoid pilot hole and was keeping the diaphragm from sealing?

I double checked that it was totally cleaned up, but maybe running air through it cleaned it out. It just seemed like it just didn't want to equalize for some reason