Quincy Air Compressor Not Building Oil Pressure?
I have a Quincy 325 that I am trying to finish up rebuilding. I got the thing put back together but have some issues.
When I turn it on, I don't get any oil pressure readings on the gauge.
I tried taking off the gauge and the unloader to see whether or not, there is oil flowing when the air compressor is on. A massive stream of oil comes out of either port when I pulse the motor
Other then trying some other pressure gauge (this one is brand new) I don't have a clue what else to try.
A massive stream of oil doesn't tell you if you have pressure, you are only showing volume, which can have very little pressure.
is there a spring-loaded pressure relief ball valve in the oil system? I'd check that first.
I believe the pump body can be indexed in one of two directions depending on crankshaft rotation CW or CCW. That might make a difference.
I believe there is a adjustment screw on the filter boss to adjust the pressure.
Depending on the ROC of the compressor, the oil pump can be direction specific. This is described in the manual. If you are positive you've assembled it correctly, then tighten the oil pressure adjustment screw, like the others said. BTW, I never see instant full pressure on mine, seems it takes the pump a few seconds to get there. But that's not a problem, as you know Quincy is designed to unload until operating oil pressure is reached.
I tried running the compressor motor both clockwise and counter clockwise with not apprent difference.
I got the oil pressure screw backed in and backed out also with no apprent difference. All the way in is full pressure I think?
Where would the check valve be? I'll look up the ROC, but its on a 1979 tank which I believe is original. The pump is a rotary vane pump.
Take a look
Quincy compressor oil pump - Yesterday's Tractor Co.
Third post from the top. Easy enough to check and could solve all your problems.
Spent some time today with the thing. Pulled the head off, some some oil around the big piston. I forgot to place this one plug into the cylinder so the wrist pin stays in place.
Went home, found this parts breakdown (attached). According to the diagram, I need to have a ball and spring acting as a check valve on the oil pressure adjustment (parts 31, 32, 33.
There wasn't a spring or ball there when I got it. Perhaps that is the issue?
What size spring and ball should I use? Is it okay to just pull one that looks about right out of my stash and see if that will work?
I'd think any ball and spring that sorta fit would be better than none! Yikes, without these parts, the thing would have been running w/ almost 0 oil pressure.
Anyway, the beauty of a Quincy is it's still supported. I'd get the OEM parts if it were mine...
X2 Quincy parts are available, they support even old units. If it was run without the ball and spring for much time expect the rod bearing inserts to be ruined at a minimum, the rod journals out of round next (that's gets really expensive). If you're rebuilding it, that implys already buying new Quincy parts: valves, gaskets and such. Get the right parts.
Originally Posted by Jim McIntyre
Inspect, clean the valves and use. Or better yet, price a set of valves for that unit from Quincy, then start cleaning!
The whole thing has been rebuilt since I got it. The prior owners spun a bearing plus the whole head was caked with carbon hence they sold it cheap.
All clean now .
I've ran the compressor in 10-15 second increments since I put it together to check function. Maybe 1-2 mins total? I got the pistons out and the crank disassembled. All the bearings look like when I put them in brand new.
I got the rebuild parts from oemair.com
Will give them (or Quincy a call today) and see what they can get me. Its just the spring and ball I need.