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PostPosted: Tue Dec 17, 2019 8:49 pm 
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Joined: Tue Dec 17, 2019 8:47 pm
Posts: 8
Hello. I got a new Crosman 1322 and have dis/re assembled it several times now. Some trial and error was incurred. The valve stem assembly (part number 760-145) broke in the following way: The delrin portion (the plastic spring guide and valve seal) broke in two sections. I got some more life out of it by using JB plastic bonder to re-attach the seal part to the spring guide part. Later, like a stupid ape, I once again hammered on the wooden dowel I was using to remove the valve, shock loading the stem, and producing the same failure as before. I have learned many lessons.

I was able to re-fasten the stem assembly again, but now the valve is holding no air at all. It expels all of the air through the transfer port, and consequently the barrel, upon the completion of a single stroke of the pumps arm. I have already ordered a replacement part number 760-145 and hope it will remedy the problem. There is some other minor damage to the valve in the form of a couple of deep scratches in its aluminum surface likely produced by the burrs on the roll pin hole in the front of the pump tube (which I have since removed).

Also, while banging on the valve from the wrong end, I dented the back of the valve, creating a burr in the aluminum which I have removed. The burr was most likely created by the aluminum impacting the steel dimple in the pump tube, which I think is there to properly locate the valve in the pump tube. Supporting this idea, I have noticed that the front frame screw is slanted when I decide to take apart the gun, suggesting that air pressure has pushed the valve back slightly further than the manufacturers intended. This is not optimal, because the transfer port will be slightly out of alignment.

Looking at the seals. The 130-035 o-ring has a shallow chip in it that almost spans half the diameter (not quite). I have decided I should replace the 130-035 o-ring just in case. The transfer port O-ring (part# 130-036) also appears to be compromised, and will need replacement. The pump cup (760-140) appears to be in perfect condition. I am testing its quality anyways by leaving the pump cocked for a while, to see how far the arm drops, if at all. One other thing I have noticed is the valve bodies threads seem looser. They were very tight at the beginning.

I tried the classic air leak test (soapy water on sealed areas) to see if bubbles would pop up in the affected areas. I suppose I should have expected the result (the valve holds no air), but their were no signs of a leak. Perhaps I have a poor understanding of this weapon and someone could give me advice or relate a similar story. Thank you for reading.

UPDATE: I am waiting for the valve stem assembly to arrive. Some new quirks have come up. I installed a new 130-035 o-ring on the valve. The original problems persist, except that after the installation of the new o-ring, the piston began making a harsh creaking sound (like the noise a ratchet screw driver makes) when the piston nears the end of the stroke. I thought that it could have been some sort of rough texture in the pump tube, so I did a tiny amount of sanding.

The noise persisted, so I put lube on the sides of the pump cup, and even some lube on the 135-035 o-ring (possibly a mistake). I also noticed that the pump arm pin had a groove in the center with sharp burrs on either side, I guess just from pumping it, so I did a couple of minutes sanding on the pin with medium grade sand paper. In the end, the pump was moving more smoothly, but I don’t know if this is a good thing. The piston doesn’t offer much resistance at this point, much less than before. It still makes a “pop” noise when it is pulled out of the pump tube though.

This lower resistance could be because the valve stem is deteriorating further, I am not sure. In its current state, I can still hear air coming through the transfer port at the end of the pump stroke. Thinking that I may have over lubed the gun, I tried to remove most of it, but the same low resistance is given by the piston. The threads on the valve are now only hand tight, so I think that over lubing may be the latest problem. Thank you for reading.


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PostPosted: Thu Dec 19, 2019 8:14 pm 
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Joined: Mon Jun 16, 2008 4:36 pm
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Location: nvvan
step away from that toolbox... lol

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PostPosted: Wed Dec 25, 2019 12:32 am 
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Joined: Tue Dec 17, 2019 8:47 pm
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walther wrote:
step away from that toolbox... lol

Why? In any case, it appears that the new valve stem assembly solved the issue.


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PostPosted: Wed Dec 25, 2019 3:50 pm 
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Joined: Sat Jan 25, 2014 9:16 pm
Posts: 1287
Location: United States
Some pix would be good. So from your description i gathered you damaged it by pounding the valve assy out by pounding on the little valve stem? If so I'd use a fat dowel w/ a hole drilled in the center of the end so it's not touching the stem.
Live and learn right? I've broken more than my share of parts, but what I learned from it was well worth it. I often stress things to failure on purpose just I can learn what'll happen. One great thing about Crosman is they carry all the parts and they're fairly cheap.
When I remove my valve I just hit the end of the tube against wood, or carpet etc. When it's near the end I can use a tool in the pump slot to shove it the rest of the way out.


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PostPosted: Wed Dec 25, 2019 7:42 pm 
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Joined: Tue Dec 17, 2019 8:47 pm
Posts: 8
Chevota wrote:
Some pix would be good. So from your description i gathered you damaged it by pounding the valve assy out by pounding on the little valve stem? If so I'd use a fat dowel w/ a hole drilled in the center of the end so it's not touching the stem.
Live and learn right? I've broken more than my share of parts, but what I learned from it was well worth it. I often stress things to failure on purpose just I can learn what'll happen. One great thing about Crosman is they carry all the parts and they're fairly cheap.
When I remove my valve I just hit the end of the tube against wood, or carpet etc. When it's near the end I can use a tool in the pump slot to shove it the rest of the way out.


You are correct, I was punishing the valve stem pretty bad. Lol, yes, after “the incident” I drilled out a wooden dowel and now use that as the valve punch. The valve seems to hold air now. I am not terribly worried as I plan on installing a new flat top valve and piston at some point anyway. I have not shot it since I got the new valve stem so I should do that. Thanks for the comment.


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