My "new" air compressor

[brawls43]

Picked up an 80 gallon Quincy two stage compressor from an auction about a month ago. Finally got it wired up and running. Runs quieter then I thought, which is nice. I checked with Quincy on the serial number from the compressor, and its a model 325, series 1, which means it was made in 1950. Kind of cool that it still works. Now its time to get it cleaned up, maybe change the oil in the compressor, get a new air filter, and figure out where the air leak is in the plumbing. Time to get out the soapy water.

 

[930dreamer]

Great find, how big is the motor? Three phase?

 

[brawls43]

It was wired for single phase when I got it. It pulls about 38A on start up, but running, about 28A.

 

[browntown]

325's are well supported pumps that from what I've read are easy to get parts for and worth rebuilding. I have my eye on an old one myself, unfortunately it has a 3-phase motor on it, so I'm looking at the expense of finding a single phase motor as well as the cost of the monster compressor.

 

[GeneralDisorder]

Add a second unloader tower and unload both the low pressure and high pressure cylinders, add a pilot valve if it doesn't have Hand mode operation, and see about upgrading to the new series oil pump with a spin-on oil filter , better pickup tube design, and hydraulic unloader port on the pump body. Also its fun to run a real three phase contactor (older NEMA units without phase imbalance protection for example) and run the start windings of the motor through the third contactor leg. This makes the machine spin down smoothly at cut-off since the start windings don't act like a generator when the clutch engages on motor stop. I hate that effect as is shakes the whole machine and is rather annoying violent IMO.

GD

 

[brawls43]

Thanks for the upgrade ideas General. I'll need to look into those. When did they offer the 325's with the second unloader? I think my motor has options for wiring as 3 phase, so I might be able to do that smooth cut-off. It definitely sounds mildly violent when it shuts off.

 

[GeneralDisorder]

You don't (and cant) wire the motor for three phase - you just wire the start windings (only single phase motors have these) through the third leg of a three phase contactor (without phase imbalance) or through the auxiliary contacts on a pressure switch so there's no induced current in the start windings when the start clutch engages on spin down.

AFAIK they have always offered dual unloaders. It's just a feature that isn't usually present to save cost.

GD

 

[Zrexxer]

Umm, is your mag starter taped to the top of the motor with packing tape?