Quincy 310-14 two stage air compressor

[Spider 2081]

Hi everyone
I'm new to this site. I am a retired Aviation electrical guy who likes working on old cars. I have a very old Quincy compressor. the tag says 310-14. The motor runs fine the pressure switch seems to work correctly but when the compressor shuts off it bleeds off all the air in the tank in a matter of minuets, I think there is some sort of internal leak in the compressor. Anyone know anything about this model compressor or a place to get information..

Thanks

 

[The Tool Tyrant]

Hi Spider. 310-14 (14= record of change aka ROC) Typical HP range:1-1/2 to 3 hp. Min. rpm: 400, Max rpm 920. Max cont. press: 200 psi, Max intermittent press: 500 psi.
L.P. bore 3.50" H.P. bore 2.00"
Go to the Quincy website and locate the manuals search page. You'll have to do a little looking, but the info is there.
That is the smallest 2 stage QR model listed in my brochure.

Regarding your leak, I would first check the check valve in the receiver. It threads into the receiver and connects the air line from your pump to the receiver. It will allow receiver pressure to return to the pump if not functioning correctly.

 

[396foxRN]

I second Tyrant's diagnosis. The last fitting from the compressor pressure line that threads into the tank.....that large fitting has a one way valve in it, and it's likely rusted open or has some debris holding the valve open. Take it off, and replace it with a brass valve.

 

[The Tool Tyrant]

Spider...Ya, when you stated "very old" you weren't kidding! The oldest parts book for the QR 310 on the Quincy website is from 1950 and includes ROC 22 & 23!
If you want to download the parts book, go to www.quincycompressor.com, click on 'Literature Library' on the top right side of the home page, Highlight 'Parts Books', type in QR310 in 'Keywords'. When the page opens, you can click on 'Details' under the cover photos which will show ROC number for that particular book.

You could call Quincy and ask if they have your ROC 14 archived. They are pretty helpful folks. Good luck, and lets see some pics of that pump!

 

[Spider 2081]

Thank you everyone for your replys. I will take some photos of the compressor and post them also I will look for the valve that is mentioned and check it out.

 

[The Tool Tyrant]

Thank you everyone for your replys. I will take some photos of the compressor and post them also I will look for the valve that is mentioned and check it out.

Spider, The check vale is very simple to diagnose, just run the pump until the receiver is full, remove the pump output supply tube from the check valve, if air is leaking out of the valve...it's junk.

 

[Spider 2081]

The compressor is not where I could easily power it up so I took the pipe off that connects the compressor to the tank. Neither the fitting in the compressors head or the fitting in the tank that the pipe connects to are check valves. Both are wide open brass fittings. The one in the tank looks like it has a step in its shape but there is nothing at all in the fitting. I believe you have pointed me in the right direction for fixing the compressor. The fitting in the tank does not want to come out easily so I will play with that first.
Thanks for everyone's quick input