Air out the barrel on resealed Blue Streak

[SADave]

Im sure this topic has been covered but the terms i searched with didnt yield any results. I cleaned up and installed a new seal kit on a late 50s Sheridan but when I pump, air just comes out the barrel. Im assuming the valve stem isn't
sealing. The insides are clean and free of debris. Any thoughts? Thanks in advance.

[Radrob]

I would say the valve stem seal too, is it installed correctly? You should see the brass side when you drop it in unless you used a Mac1 kit then it's installed with the X facing up.

Just guessing but post what kit you're using and I'm sure someone will help. Good Luck.

[SADave]

Right now it's got the Mac1 kit in it. I tried earlier with the parts from pyramydair and had the same results. Ive got the x facing up on the inlet valve and tapped it. I was thinking it might be the exhaust valve stem since air is getting by and goin into the barrel. Im no expert though.

[Bentong]

Try cocking first then pump it.

[Radrob]

+1 on cocking it first.

Did you clean it good and do you have the half ring hammer, if so did you install it with the ring facing down?

Did you see these instructions for seating the valve?
My Check valve(inlet) is the best ever. Hit it good to seat it with X visible. Use a solid drift just smaller in diameter than the check valve and strike it good so it is smashed into the seat. Make sure you are not trapping any debris when you do this. Cleaning the thing out is the key to a quality job. I soak it for weeks before I attempt to remove the crud. Some guns are completely impacted with debris as they were NEVER LUBED and consequently never cleaned themselves. They go down because of corrosive and/or congestive debris.
Scroll to the bottom of the page.
http://mac1airgun.com/rebuildpartstechniques.html

[SADave]

I saw the directions for seating the valve, I tapped it pretty hard, may give it another go later.  Ive pumped with the trigger unit off so there is no pressure in the valve and pumped it while cocked as well.

[oldair]

Your problem is not the inlet check valve, but the exhaust valve.  The slightest nick, debris, or irregularity on the valve seat surface can create leakage.  Presumably your rebuild kits included a new exhaust valve, so it isn't likely the seal itself is the issue.  I suggest you remove the innards again and polish the brass exhaust face to make it completely smooth, clean, and uniform.  Then remove any schmutz generated in the polishing process and reassemble.

[longhunter]

Another possibility is, the valve nut isn't tight enough, or, did you put two seals in front of the valve???
Also, DON'T wack that Mac1 intake seal too hard. A couple of light taps are all it takes. Too hard, and you'll split the sucker.

[SADave]

Im not sure at this point what's wrong. The brass valve face of the body is clean and I polished it. I swapped valve body and stem from another gun and its still doing the same thing. Im pretty sure I've screwed the retaining nut in all the way and I checked to make sure  there is only 1 seal. Ill clean it out one more time and if it doesn't seal I'll send it off to get fixed.

[Radrob]

Watch this vid and maybe it will help, it's not a Dan but it's close enough so you can understand how it works. I hope you get her done.

[BrushPopper]

Some posters have reported good results by dribbling a little Mac-1 secret sauce into the valve-works.

Haven't tried it, myself. I try to keep a bottle or two always on hand
BP

[Rob112o]

Next time you remove the valve stem. Check the pliability of the rubber on that valve stem. I've gotten new kits and that rubber at the base has been hard.