Originally Posted by
seki
Ichudov, it sounds like your machine is doing the same thing mine (a Bridgeport Series II Interact with pneumatic speed control) was doing. On my machine, one of the O-rings on the end of the spool had hardened because the machine is so old, and it wasn't holding enough air pressure. To determine this, I ran it with the valve end caps loose. Lots of air came out from one cap, not much from the other. Don't run it with the end caps removed, or the spool might come shooting out and then you will have a bunch of missing and broken spacers. I recommend that while you have the valve disassembled you replace all the questionable O-rings. You can get an O-ring kit at Harbor Freight or Northern Hydraulics (Northern Tool?) and many other places. Good luck!