I am new to this forum but can anyone tell me how to replace a check valve on my 500 cc .25 Sumatra. I have replaced the original fill probe with a foster quick disconnect from Pyramid. The gun will take air up to 3000 psi but after approximately 2 days it is back to zero. I have a .22 cal Sumatra that is a year older and have never had any problems. I have quite a few airguns but I have never worked on any of them. Any help would be greatly appreciated. Thanks, Jim F
Replace check valve in .25 Sumatra airgun
- Thread starter JimF
- Start date
Never owned one but I'll guess and some owner will come along soon.
Same idea as the Carrer 707 rifle ( have owned those),
Make darn certain NO air remains - right yours leaks but maybe it held the last 100psi?)
remove the spanner nuts, nice to have a real spanner wrench but perhaps you can rig some thing, thread protector cap off, smack barrel band with soft (rubber/wood) mallet, remove, several o-0ring under there replace them all just cause,
Same idea as the Carrer 707 rifle ( have owned those),
Make darn certain NO air remains - right yours leaks but maybe it held the last 100psi?)
remove the spanner nuts, nice to have a real spanner wrench but perhaps you can rig some thing, thread protector cap off, smack barrel band with soft (rubber/wood) mallet, remove, several o-0ring under there replace them all just cause,
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Spysir.....Thanks for getting back to me. Yes, I had a scary episode with an "empty" CO2 cartridge about 35 years ago in an old Crossman gun so I learned the hard way. 100 psi is still almost 7 BAR. I think I will buy the spanner wrench as I don't want to mess up the finish. I also will order the check valve and have rubber mallets. Thanks again for your help. Jim F
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I've never had to change one on my Sumatras. You can call Boris or Stacey in the tech section at Pyramyd Air, they are pretty accessible and will explain how to do it.
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