Hey guys I am fixing a 392 Benjamin pump and I completely resealed it put it back together and when I pump it air gets pushed out the barrel what am I missing did I assemble the valve wrong or is the valve spring weak? 
HELP! Benjamin 392 leaky valve?
- Thread starter TheBullsEye
- Start date
Haven't rebuilt a benji but when I did my Sheridan a bit of brass came off the threaded nut and lodged in the valve making it leak. I took it apart and removed the shaving and all has been good since. Does the valve come out on the benji or is it soldered in like the Sheridan? Either way take it apart and look for shavings or crud in the valve.
Did you have any instructions or take pics of how the valve came apart? It 's not impossible to mix up the order of seals and springs....
Did you have any instructions or take pics of how the valve came apart? It 's not impossible to mix up the order of seals and springs....
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Thanks for the reply I tore it apart again and looked at the valve I have it together right no gunk or shavings that I saw but upon further testing when I pump if I put my finger over the barrel so the air doesn’t come out the back pressure leaks out around the valve like back by the trigger area
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Maybe try cocking the hammer, then pumping and see if that makes a difference. Here's a link to the owner's manual and parts diagram-https://support.crosman.com/hc/en-us/articles/203361554-392-Owner-s-Manual-EVP-2007-2015-
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I tried the hammer cocking it’s ether leaking past the valve body or past the stem or maybe through the middle seal on the valve
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Well I got it I seal by pumping short strokes until I felt it build up air pressure but I managed to ruin 3 seals in the process of taking it apart a million times ?
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Glad you got it figured out! Nothing quite as frustrating as having to redo something several times. Also, great planning by having those extra seals around, beats waiting weeks for new ones....
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