Which Model Quincy Compressor?

[DougWil]

I am looking to put a quality 2 stage compressor in my home shop.
It can be up to 7.5hp 3 phase.
Plan on occasionally using it to supply air to a blast cabinet.

I have grazed through quite a few Quincy threads but don't see some of the info I would like to know.

Which models would be recommended?
Which models are parts more easily available?
Any eras or models that should be avoided?

Seems like typically these old Quincy's are found for sale parked in storage without any power, or at least no 3 phase.
So I would be buying with a lot of unknowns, priced accordingly but don't want to haul something home that is unrebuildable.

I have lots of mechanical experience so old doesn't scare me.

 

[zkling]

QR325 is their flagship for small shops, step up to a QR370 or even 390 if you really need the output, but you will be limited with the 7.5hp.

Avoid the QR2xx series as they are single stage and only designed to run at ~110psi max. I'm running a 270, the single stage is a bit of a pain at times (high duty cycle).

 

[Brad J.]

The 340 and 350 pumps usually are teamed with a 7.5hp or 10hp.

I don't believe they made a bad one. I have a 340 with a 7.5 single and a 350 that is pto driven.

Don't shy from a 370 or 390 as they can be run with a 7.5hp motor with the right pulleys. They would probably be at the minimun 400 rpm's but they would a be a sweet deal because they are quite at low speeds.

I have a 325 running with a 3hp motor at 500 rpm's and it's nice a quite. I use it daily for paint and general air but turn the 340 on for the blast cabinet.

 

[justanengineer]

JMO, but my main suggestion would be to get a pressure-lubed Quincy bc the splash lubed heads are cheaply made by comparison. The oil pump should be easy to see, its driven by the crank on the opposite side as the flywheel. If you find a steal and cant hear it run I wouldnt worry, it should spin fairly easily and smoothly by hand, worst case if it sounds good it might need a few hundred in bearings/bushings/seals and overhaul is fairly straightforward. The same applies to 3 phase motors - if it spins smoothly/quietly its likely good and easily rebuilt regardless. The rest is just plumbing and common parts, take it all apart, clean, and reseal the joints.

Best of luck.