Toro Sprinkler valve - performance issues

[zvallance1]

So i made a new mini pnuematic about a week ago...little soda bottle chamber, modded valve, etc.

now, usually its a beast and shoots 100 yards at 60 or so PSI, but for some reason when i went out to shoot some potatoes (about 15 min ago) the potatoes wont even leave the barrel (this gun has an acceptable 1.5:1 ratio, so its not the gun's dimensions that are screwing it up)

ive made quite a few pnuematics already, but this is my first attempt at a modded valve since my first failure at modding one (never figured out what what wrong with that...oh well..)

so, can anyone lend a helping hand and get the beast back in working order?

[Benny]

well, whats the matter, is there air leaking out the barrel, is it leaking, what the hell do you mean.

[zvallance1]

like i said, the problem is that theres was a sudden, drastic, decrease in performance and i have absolutely no idea what happened.

[rna_duelers]

I believe the 1.5:1 is only used on combustion a ratio of 4:1 is said to work well on pneumatic maybe the slugs are a to tight fit in the chamber and causing alot of friction,try lubing your barrel or use a cut down section of barrel and see how it goes and if it works well increase your C:B.

[CS]

R_D- Hes obviously stating that everything else has remained constant (pressure, ammo, conditions, etc) so it seems as if the valve might be reason for reduced performance.

Z1- All I can suggest is you remove top and search for possible problem. Im guessing the time is longer required for the "air" to dump threw the valve? Give us a method of operation and what happesn at each method.

[zvallance1]

Give us a method of operation and what happesn at each method.

would you like a step by step? from loading ammo to firing? or just whats going on with the valve

[)DEMON(]

mabey you have leaky connections

[zvallance1]

mabey you have leaky connections

if i had a leak it wouldnt have just shown up, and itd have to be one helluva leak to get the decrease in performance that im experiencing

[CS]

Demon, no one is so dumb as to miss a leak that alllows 95% of there air through it...

Z1-Like ill show you below: (Just made up)

>Gun at rest-0 PSI
>Fill chamber with air via small compressor- ~100PSI- Small yet recongiziable leak has sounded from valve> Gun also seems to be losing some PSI from the leak.
>Blowgun vent is acivated- seems longer then usall to vent
>Potato fails to exit barrel.

Basically, state each step/ process, then anything that is different from previous working condition. So if there is something wrong hopefully we can pick up on it via the change from norm.

Just a hunch:
Does your blowgun seem not to expell as much air? If so check under side and blowgun its self for obstructions reducing flow. Have you even dismantled the valve to inspect for problems?

[zvallance1]

actually pimp, what you said was right...all those steps were dead on...
couple things to metion though..the little leak seems to be coming out of the barrel which led to me to think that the diaphragh didnt seat properly...i took it out, cleaned it off, and then stretched the spring a bit in case it had been compressed to the point that it wasnt fully going back to it's initial shape....that didnt do anything though...still that little leak (drained the gun from 60PSI to ~24 in 3 minutes)

also, when i go to activate the blowgun, it doesnt vent the entire chamber...rather, ill have it open for ~.5 sec which will take it from 80-27PSI...another half sec will take it from ~27-15 then the last time will dump the remaining pressure...
seems kinda like a primative hammer valve
(that May or may not have been happening before the decrese in performance...i hadnt paid attention to it though)