quincy 310 compressor unloader

[jniolon]

I’ve got a Quincy 310 roc 24 compressor that just started giving me trouble.... unloader is doing just that... and it won’t build pressure... worked fine yesterday, today it just blew me off...literally.
Oil level is full... pressure is 20 psi. I’ve taken the unloader apart and everything is moving freely and shows no abnormal wear... but something isn’t moving to close off the unloader, I guess...

Quincy tech told me the check valve was the problem... took it apart and sure enough... washer was in pieces, so no seal. ordered/installed new duplicate check valve and problem is still there... so I'm backing up the pipe to the unloader valve on top of the compressor head...

it's connected to a 'pilot' valve on the side of the compressor by 1/4" tubing and the pilot valve is fed by 1/4" tubing from below the check valve (tank i/p) when I disconnect the line between the pilot valve and the unloader
I feel air pressure at the unloader end of the tube and the unloader closes and it will build pressure...so it should be getting a ‘signal’ to stop unloading, right ???

any quincy guru’s or can someone help me trouble shoot this problem ??

anyone... anyone ????

 

[MacMcMacmac]

Pull the valve from the crankcase and replace the seals. when they wear the oil just leaks by them and back to the crankcase and does not pull the piston in to close the air to the unloader tower.

 

[jniolon]

Mac... I'm assuming you're referring to the unloader valve in the 4th picture... is it above the crankcase oil level or do I need to drain the oil before removing

 

[MacMcMacmac]

Mac... I'm assuming you're referring to the unloader valve in the 4th picture... is it above the crankcase oil level or do I need to drain the oil before removing

You can pull it without draining the oil.