Old Champion 2 Stage compressor issue

[Gizmosity]

I picked up this beast about a month ago. I took the motor and pump off the tank and tested the tank. I replaced a couple pieces of pipe and basic fittings as well as the gauges (which don't seem to work).

The issue I'm stumped about is the pump. Before I bought it I ran it in the previous owners garage. Because of its age (and the previous owners age/memory) I didn't take it to full pressure, but rather just turned it on, got the pressure up to about 40psi, then shut it off. I moved some other equipment I was also buying for about 30 minutes, came back and saw it was holding pressure and then loaded it and took the load home.

I just got a circuit run so I can operate it after I put the motor and pump back on. The issue is that there's a fitting on the pump that is bleeding air. Didn't do it before. I was pretty careful taking it apart and putting it back together. The fitting leaking air is in the center of the photo pointing down and looks like an adaptor to step down from 1/2" pipe to 3/8" or so. It's got some sort of plug in it I would assume is pressure sensitive. It's a substantial amount of air coming out. Any ideas what this particular fitting is for? Why it's blowing? What to do about it? I've sent an email to Champion Pneumatic to see if there is available documentation and parts availability for the pump but have yet to get a response.



Any ideas/help/info would be greatly appreciated. This is the first 2 stage compressor I've owned so I'm stumped.

 

[Fixnair]

That is the centrifugal unloader. It is open while stopped and closes when compressor is running. If it leaks while stopped it is because the check valve in the discharge line is leaking tank pressure back against the compressor. Replace the check valve.
If it leaks while running it is because the valve inside the reddish colored hex is leaking. Probably a piece of trash in it. When you remove the hex you will see a small spring which bears on a small ball inside the brass valve. Careful to not loose it.
If it still gives you trouble you might want yo remove the six screws around the housing, also remove the tube. The works are pretty simple, you'll see the fly-weights and the little pushpin that pushes the ball off it's seat. When putting it back together you may want to use some locktite gasket eliminator or silicone glue.

 

[Gizmosity]

Thanks for the info. I will turn it on again in the morning and see if it's constantly leaking or intermittently leaking. It sounds like I at least need a new 1/2" check valve.

 

[Gizmosity]

New check valve and hopefully some usable gauges from compressorsource.com


Might actually have a wired and working compressor this week!

 

[Carlav1410]

Hope you don't mind me chiming in on an old post.. Can I ask a question?

 

[Gizmosity]

Ask away.....