PDB air "leak" from the control valve?
Wondering if anyone else has a constant air "flow" audible from their PDB control valve? We've checked all of the fittings on the outside in and out, and the needle valves, etc. This "leak" or "flow" seems to be originating from inside the valve box. It's not like the tiny leaks that you'll sometimes hear from a compressed air fitting but a fuller high flow type sound. Definitely enough flow to require the compressor to come on more frequently than every 30 minutes or so it usually cycles at.
We have regulated 90psi service to the valve and the PDB is functioning normally otherwise.
Is this normal??
Re: PDB air "leak" from the control valve?
No, its not normal, but also not unusual for solenoid pneumatic valves. You can CAREFULLY disassemble the valve (there are springs and other small parts inside, and orientation of several parts is critical), removing the "shuttle", which has several O-rings on it. Slather some silicone grease (available at any auto parts store) on the o-rings, and re-assemble. If that does not fix it, you can try replacing the o-rings, though they may be an oddball metric size.
Regards,
Ray L.
Re: PDB air "leak" from the control valve?
After 5 years of use my PDB control assembly has developed a leak similar to what you're describing. I have not attempted to diagnose or repair it yet. Compressor with a 20 gallon tank cycles about every 30 minutes or so also. Kind of annoying.
Re: PDB air "leak" from the control valve?
Thanks for the replies!
This one is brand new out of the box from Tormach so we'll let them know for QC and then I think we'll attempt to disassemble and grease it as SCzEngrgGroup suggested. I'll post back here with results.
Re: PDB air "leak" from the control valve?
If its brand new, i'd get it replaced before opening it up and voiding any warranty it might have.
Re: PDB air "leak" from the control valve?
Tormach does sell a seal kit for the power drawbar air cylinder:
https://www.tormach.com/store/index....show&ref=32093
and NYCNC did a YouTube video on rebuilding the 1100 power drawbar.
https://www.youtube.com/watch?v=gkE0vk_oDAU
Re: PDB air "leak" from the control valve?
Quote:
Originally Posted by
GreenLightGo
Wondering if anyone else has a constant air "flow" audible from their PDB control valve? We've checked all of the fittings on the outside in and out, and the needle valves, etc. This "leak" or "flow" seems to be originating from inside the valve box. It's not like the tiny leaks that you'll sometimes hear from a compressed air fitting but a fuller high flow type sound. Definitely enough flow to require the compressor to come on more frequently than every 30 minutes or so it usually cycles at.
We have regulated 90psi service to the valve and the PDB is functioning normally otherwise.
Is this normal??
Not normal, I had that too. Tormach replaced it and the new one was fine. I used to build pneumatic systems commercially, and that happens more than you would think with new parts.
Re: PDB air "leak" from the control valve?
Quote:
Originally Posted by
Spinnetti
Not normal, I had that too. Tormach replaced it and the new one was fine. I used to build pneumatic systems commercially, and that happens more than you would think with new parts.
Mine has leaked air since new, a bit over 5 years ago, I thought it was the cylinder orings, never checked it out. Maybe just a new control valve is all thats needed?
Re: PDB air "leak" from the control valve?
Mine started leaking air a year or two after I first installed and I'd been running it "dry" since that's what the manual instructed. Tormach tech support told me that they had been misinformed by the air cylinder manufacturer and that they now recommended running the PDB with "oiled" air so I installed one of the FRL kits from Tormach and re-built the cylinder with their seal kit. I've had no leaks since then. FWIW, the old seals did look a bit worn.
Re: PDB air "leak" from the control valve?
Michael,
Did you replace the seals in the PDB cylinder or the control valve?
Re: PDB air "leak" from the control valve?
Quote:
Originally Posted by
IMT
Michael,
Did you replace the seals in the PDB cylinder or the control valve?
Just the cylinder seals. I haven't had a problem with the control valve yet.
Re: PDB air "leak" from the control valve?
i have recently got a leak on my powerdraw bar, and like the original poster said, its a big leak that seams to be coming from the button valve area. i got a replacemtn push button valve from tormach for $20 and replaced it. that didnt fix the problem though, and has lead me to do some more digging. although the air "leak seams to be coming from the button area, i believe whats actually happening is the large drawbar cycliner is binding/ not closing properly and leaving that air line open. im gonna take the cylinder apart tonight while wathcing the nycnc video. gonna see if i can get away with a clean and lube, but will order a rebuild kit if any damage is seen.
