Page 1 of 2

sprinkler valve equalization hole trouble?

Posted: Tue Aug 12, 2008 3:12 pm
by spencetron
*I have already read the FAQ, and tried my best to fix the problem on my own*

I have a modded 1" orbit watermaster on my new (and first) pneumatic cannon, but every time I go to fire it air just leaks out the pilot. I tried removing the plastic tab on the equalization hole, putting tape on half of the hole, putting a "U" shaped metal rod in the hole, and lithium grease on the diaphragm (desperate). I checked the diaphragm for other holes but there are none. It is getting very frustrating, is there anything else that could be causing this?

Posted: Tue Aug 12, 2008 4:07 pm
by psycix
-Is your pilot valve large enough?
-The hole is best sealed off with epoxy.

Posted: Tue Aug 12, 2008 9:32 pm
by spencetron
psycix wrote:-Is your pilot valve large enough?
-The hole is best sealed off with epoxy.


-Im using a (heavily) modified blowgun. the internal rod thing has been filed down, the holes in the other internal part were drilled to increase flow. But there is a 2"x1/8" threaded brass tube on the end where the nozzle would be to accommodate a epoxy hand grip.

-Dont you need the equalization hole?

Posted: Tue Aug 12, 2008 10:26 pm
by nivekatoz
I think hes talking about the place where the solenoid gos. Epoxy that hole.Not the equalization hole on the diphram.

Posted: Tue Aug 12, 2008 10:28 pm
by spencetron
nivekatoz wrote:I think hes talking about the place where the solenoid gos. Epoxy that hole.Not the equalization hole on the diphram.

I removed the solenoid and filled that entire cavity with 5min epoxy.

Posted: Wed Aug 13, 2008 12:46 am
by clide
Are you sure that your mod isn't interfering with the diaphragm movement?
Do you have a bunch of hose between the sprinkler and your blowgun?

Other than that make your equalization hole as small as you possibly can without blocking it completely.

I'm a little confused as to what type you have. Is the equalization hole in the center or directly on the rubber diaphragm? I believe the bent metal rod suggestion is for when the equalization hole is in the center, but the ones that have the plastic tab have the equalization hole in the diaphragm.

If the hole is in the diaphragm then put the plastic tab back in if you still have it. Removing it is only for when you are having trouble getting the valve to seal. Personally I've never had to remove it.

If you continue having problems then some pictures may help us diagnose it.

Posted: Wed Aug 13, 2008 8:46 am
by spencetron
clide wrote:Are you sure that your mod isn't interfering with the diaphragm movement?
Do you have a bunch of hose between the sprinkler and your blowgun?

Other than that make your equalization hole as small as you possibly can without blocking it completely.

I'm a little confused as to what type you have. Is the equalization hole in the center or directly on the rubber diaphragm? I believe the bent metal rod suggestion is for when the equalization hole is in the center, but the ones that have the plastic tab have the equalization hole in the diaphragm.

If the hole is in the diaphragm then put the plastic tab back in if you still have it. Removing it is only for when you are having trouble getting the valve to seal. Personally I've never had to remove it.

If you continue having problems then some pictures may help us diagnose it.
My blowgun is directly attached to the valve. And my equalization hole is on the diaphragm itself. I made the mistake of trimming the "nozzle" part off the tab, thus destroying it. I wanted to find a temporary solution before I epoxied most of the hole, so I can figure out if its the hole that is actually causing the problem. and the mod is in the center of the spring, in a little cavity that wouldn't get in the way of anything.
I don't understand why my valve is giving me so much trouble, could the male threads attached to the valve be leaking pressure? Or would that just cause the valve to be constantly piloted?

Posted: Wed Aug 13, 2008 5:29 pm
by clide
Do you have that the plain looking green Watermaster valve? The diaphragm on those has a big white knob sticking out of the top that goes into that little cavity in the center of the lid.

Leaking threads wouldn't be causing the problem you are describing.

Something is definitely not right if a modified blowgun connected directly to the valve isn't able to pilot it. Even without the tab in the diaphragm it should be able to actuate it easily. Are you sure that the diaphragm is seated in there properly?

Posted: Wed Aug 13, 2008 6:52 pm
by iisthemuffin
Where is it leaking from? Is it leaking out of the end of the blowgun? I saw that you said something about 1/8 inch nipples. Is your blowgun on right?

If its leaking out of your blowgun, you most likely messed something up while modding its internals. Try taking an unmodded one and throwing it on there. See if you still have the same problem.

Posted: Wed Aug 13, 2008 9:02 pm
by spencetron
muffin- When I pull the trigger, air is leaking out of the end of the blowgun, where the nozzle would go. I know I have the blowgun on there right, I just mixed up the thread size when typing this. ill try it with a different, Unmodified blowgun, but I didn't think the pilot has anything to do with this problem.


Clide- yeah, I have the plain jane green orbit watermaster you are describing. I kind of push the diaphragm into its seal, then screw the valve lid on. unless there is some super-special way to seat it properly, I think I'm doing it right.

Posted: Wed Aug 13, 2008 10:34 pm
by iisthemuffin
It sounds like your diaphragm isnt actuating.

The air is supossed to come out of the blowgun. Thats why it is a pilot. But just as soon as you pilot the valve it should open.

From what you told me, it seems like ALL of your air is coming out of your pilot. And if the air is coming out of your blowgun and not the barrel, your valve is sealing just fine.

I saw you said you kind of push the diaphagm in. Im not sure what you mean by that. But do it once without pushing it down (or whatever it is your doing) and see what happens.

Posted: Thu Aug 14, 2008 12:48 am
by starman
I'm surprised you're having this kind of problem with this sprinkler. This mod is fairly straightforward and has been successfully completed 100s if not 1000s of times by many a spudder.

Posted: Thu Aug 14, 2008 4:59 am
by psycix
A very simple but forgotten question:
What pressure are you currently using?

On too low pressures, the pressure may be too low to get it actuate.

Posted: Thu Aug 14, 2008 8:53 am
by spencetron
starman- Im just as confused as you, id know I did the mod perfectly.

psycix- Ive tried just about every pressure between 30 and 120 psi, all with the same results.

muffin-Ill try that, but I doubt its seated incorrectly.


Its like the diaphragm is "stuck". When I pilot it, it just doesnt budge. Air just slowly escapes out of the end of the blowgun.

Posted: Thu Aug 14, 2008 8:57 am
by iisthemuffin
Is your valve on backwards or anything?