strange benjamin handpump issue

[alex77147]

Hey guys, I have had my benjamin handpump for a while and every now and then had to replace the 007 oring that commonly wears out on these pumps, after replacing the worn out oring pump would do its job without any issues.  Well recently it quit working, the symptom is the pump will blow out of the intake on the downstroke, usually when he tiny 007 oring fails it is hard to pull up but not in this case.  The pump seems really simple but for some reason I cannot just get a grasp on how each stage works and what faulty component could cause for it to blow out of the intake on the downstroke.  I'm supposed to go camping within a few days and i'm really upset that it quit on me now, any input is greatly appreciated guys and gals!

[Roadworthy]

If you get a good response here, that's great.  Sunopticsusa repairs these pumps.  You might call them.  They can be very helpful.

[cobalt327]

Something might be causing the check valve to stick open. That would be the first place I looked, anyway.  Good luck.

[alex77147]

the valve with the spring or the ball up top? I can hear the ball working when I had the pump partially apart, check valve seems to be working as well(i can hear a pop and on the downstroke if I don't have the pump hooked up to anything).

[cobalt327]

The conical w/spring. What about the nearby O-rings? I saw somewhere replacing #10 helped a problem like yours... but the 'fix' might have been coincidental to having disassembled the valve.

[alex77147]

The conical w/spring. What about the nearby O-rings? I saw somewhere replacing #10 helped a problem like yours... but the 'fix' might have been coincidental to having disassembled the valve.

well thanks man, ill give it a try right now, I think I have a spare, now to take it apart for like the 50th time since yesterday haha.  I'm getting good at taking this thing apart.