2240 pistol degassing problem, please help????
It’s late and I am throwing in the towel hoping to wake up in the morining with some sound advice.
I am trying to build a 2240 pistol and I am using a disco valve (but I also had the same problem with the stock crosman valve) all stock internals. I am getting a good puncture hole in the 12 gr carts, but the minute I fire the first time it lets all the gas out. I took it apart and could not seem to figure out anything wrong, so I put it back together and once again…total gas dump????????????
One thing I noticed is that the new Crosman valve face o rings have a much wider hole than the old ones I have….but again, when you hold a cart up to it they seem to seal properly. I am also torquing the end cap down firmly. What would cause the valve spring to not seal the valve stem after the hammer strike???
I appreciate your help as I would like to get this one together…it is a gift for a buddy 😥
All Replies
Do post some pictures when you get it to a reasonable stage. Will be quite interested in seeing what you did.
Carl
Is this a completely stock 2240? No valve mods or any other work?
Carl
Yeah, completely stock. So it is surely that nipple/valve face. Why, I haven’t a clue. If you look at them, they seem perfect. In fact, they are practically brand new. 😯 ❓ 😯 ❓
I even tried a variety of o rings (including the ones it came with) I used plenty of teflon tape…the odd thing is it finally sealed for a moment that is. I put it down on the bench, then a few moments later it started hissing away. I could see that it was coming out the front by the valve face….
All this frustration made me tear down my stainless 2260 pistol and turn it into a carbine. I spent three hours fabricating a chrome/stainless/billet shoulder pad and cheek rise (from a variety of parts I had left over in my garage/hot rod bin). It is looking nasty. I am off to HD to get some stainless hardware 😎
Well I must admit that beats all I’ve ever seen or heard. Something is still stinky in Denmark but at least for now you have the problem narrowed down to possibly one thing.
Is this a completely stock 2240? No valve mods or any other work?
Carl
Man,
I’m not having a good day. I just found out the old ladies airconditioner in her piece O’ crap durango needs another 1,000.00 worth of work. That on top of money already spent on a new compressor and condenser fan motor….I tried to do it all myself, but alas I aint about to take the entire dash apart to get that evaporator box out…and that is what needs to be done. 7 hours labor at least 😥
I have deduced the problem with the 2240 to be something to do with the valve face nipple or rubber seal (the odd thing is I used two different valve face nipples and two different rubber seals, interchanged four differen t ways and still same problem 😯
I figured out that the valve stem is fine by using the same valve stem and the same valve in a bulk fill set up with 900 psi of air in it. It is holding air and it functions as it should when I tap on the stem with a dowel.
I even set up the co2 valve in a 2250 tube just to make sure it wasn’t the tube or end cap, etc. and the same problem occurred in a proven tube and end cap.
That said, it has to be the valve face/nipple/rubber seal. It is just odd that with the two different (stock crosman) valve face/nipples and the two different rubber seals…I am having the same problem. I guess I will be forced to order some new valve face/nipples from Crosman. Maybe I will give the gun to my buddy set up as a pcp (until the parts come) as long as he does not fill past 900 psi he should be fine, or so I’ve heard 😕
[color=red]The small hole is a bleed port that prevents the seal from being “blown” out of its seat by a burst of high pressure gas such as when a charged powerlette is vented into the gun to remove it.[/color]
Carl
Thats funny, I thought that was to aid the removal of the rubber seal. Hey it does work great for that as well…preventing you from “mangling” the seal. I’ll post my findings later after I have my coffee and get my kids off to VBS. Thanks!
When I was learning about the 2240 valve I became curious about that little hole and finally got an answer from Crosman.
[color=red]The small hole is a bleed port that prevents the seal from being “blown” out of its seat by a burst of high pressure gas such as when a charged powerlette is vented into the gun to remove it.[/color]
Carl
Sorry guys, I did not mean to call it an O ring. Yes it is the same orange flat rubber that you have. It is the stock Crosman piece that they sell. The valve face is also a stock Crosman piece and I purchased the face (the nipple holder) with the O ring.
I compared it to an Older valve face that I had from a used gun I bought and the circumference of the older one was much smaller than that of the new one.
Yes, I recall that it was very difficult to remove the “rubber piece” from that one as well. I assumed that is what that little hole is on the side of the nipple. Once I put a small pin in there it helped to break the seal and lift the piece out….
Neither valve is modified.
I have a stock crosman valve and a stock disco valve and I tried both valves with the same valve face and they both degassed. I also tried two different valve stems in both and the same problem is evident. Tommorow I will Put the bulk fill valve face on and see what happens. If it does not degass then the problem most difinitly lies with the valve face/nipple/flat rubber washer seal….
Also, the nipple is very soft and I can actually bend it a little to help hold that rubber piece in place. I have an extra one that I can try it on in case I ruin it…but I don’t believe it will hurt it I will not “crimp” it to the point of causing the rubber seal to rise up off of the valve face….I’m off to bed…good night guys, and thanks 🙂
That o-ring seal in the valve that the nipple seats against should not ever fall out. That it is doing so definitely is a problem and could be the source of all your valve woes. But then it really is not an o-ring but more of a flat rubber washer made of some Crosman unique rubber. Are yours really o-rings? Mine are an off orange color. What color are yours?
But didn’t you say you have two stock valves and they are both doing the same thing? Are both the o-ring seals falling out? That would be too weird.
Have you modified the valves in any way?
Carl
you indicated “One thing I noticed is that the o ring fits loosley in the nipple. Not loose enough to be the “wrong size”…but loose enough to fall out after it degasses…”
At least in the stock valve I had to pry the thing out. Almost to the point of destruction.
Even when I was having leakage Peloil seemed to temporarily stop the leak, but it sounds like it isn’t the case foe you.
I did a quick google image search to try to find a good image of the end of the valve but to no avail.
You might want to email the folks at Bryan and Associates, they are good people and helped me with some answers during my mod. Granted I bought a bunch of parts from them but they are VERY nice folks.
Ben
thanks for the link. I actually tried those parts as I have more than one. I even tried a stock crosman valve…still same problem. this is proving very difficult to pinpoint. I will have at it again tomorrow.
I don’t know for sure if the disco valve is built the same way as a stock 2240 valve but I had to replace a couple of parts before I was able to correct a similar problem. Here’s a diagram of the valve:
Damnit it won’t paste in. So you’ll need to go here: http://www.crosman.com/pdf/manuals/crosman/2240/C2240-EVP.pdf
I replaced parts 2250-016, 778-061, G397-012. I think the last one was the issue but since I changed three variables I don’t know for sure which it was.
Good luck, a 2240 is a nice gun – I sold mine to buy my TSS.
Ben
I couldn’t wait till morning. I went out. Made sure the piercing cap was tight, made sure the valve halves were tight.. Still degassing. The cart seems to be seating nicely against the fill nipple by the looks of the indention it leaves behind when I take it back apart…this is driving me nuts 😡 😡 😡
I have a way to do some deductive testing. I am going to put a bulk fill tube (and valve face) on it and set it up as a bulk fill and fill it to 1000 psi. If it holds air, would’nt you say that the problem is with the valve face/nipple??
Thanks Carl,
I did not see your posts…all of a sudden they just appeared all at once 😯
I did try the oil on the nipple o ring. One thing I noticed is that the o ring fits loosley in the nipple. Not loose enough to be the “wrong size”…but loose enough to fall out after it degasses…
I noticed that the old o rings I had from a used cart gun fit much tighter in the nipple and they had a smaller diameter center hole.
I’ll try out your suggestions in the morning. I’m going to put the valve in without assembling the gun and then I’m going to use a dowel to pierce the cart this way I might be able to see where the gas is coming from, maybe, that is.
The 2300 is .177 and that spacer is used to reduce the valve volume so the shooter can get more shots per powerlette/cartridge.
Carl
- You must be logged in to reply to this topic.
Do post some pictures when you get it to a reasonable stage. Will be quite interested in seeing what you did.
Carl
worked on it some more this moringing. I hope to finish it tonight and I will post pictures. 🙂