txvwnut
Well-known member
I actually have one of those hidden in the back of my office. Mine is missing the oiler bottle.

Very odd. Are those domes the air chambers and the piston rods are exposed?Here's a weird one (to me)
Any progress on this?Thanks Dan
I rolled up on it one morning on my way to a swap meet. It had popped off the ball of the truck that was towing it to the swap meet. It was laying on its side still attached by the safety chain. After about a 1/2 hour of fighting it we managed to get it back up on her tires the guy started it up for me and we made a deal right there on the street. He brought it over after the meet . it pumps 200 lbs of constant pressure and runs like a clock.
I'll be doing the body work and putting a paint job on it this summer
I've got bad pumps with good motors and the opposite - no bad tanksBut the pump!![]()
I have a good motor and pump but it had a bad tank.I've got bad pumps with good motors and the opposite - no bad tanks
RonDon Long
How loud is that unit? Can it be run early morning or evening without the neighbors being irritated.
Really looks nice on that pad.
Ron
i've got a 25HP version of that at the shop. that's clearly a quincy 2 stage with an oil pressure unloader.
I posted in another forum here and got a different reply can you confirm?i've got a 25HP version of that at the shop. that's clearly a quincy 2 stage with an oil pressure unloader.
It's a single stage - look at the head - the intake is on one side, and the discharge exits on the opposite side and goes right into the tank. Notice that there are no intercooler piping loops on the far side of the pump.i've got a 25HP version of that at the shop. that's clearly a quincy 2 stage with an oil pressure unloader.

it's got two unloaders, which screams "two stages" to me, but I supposed it could just be two piston single stage. Intercoolers are sometimes optional, especially if it's a lower speed pump because it's running slow (which that picture makes it appear to be). Maybe if I had a better view of the head I'd have a different opinion but that's my take based on looking at it.It's a single stage - look at the head - the intake is on one side, and the discharge exits on the opposite side and goes right into the tank. Notice that there are no intercooler piping loops on the far side of the pump.
So being a QR-series pump, it's a 2-series model pump which is single stage (two stage model #s start with a '3'). It's hard to tell the scale on this, but here's a list of single stage models - check on the side of the pump crankcase opposite the motor, there should be a label plate stamped with the model and the revision code AKA the Record Of Change or ROC:
I would wager from the picture that this is at least a 240 pump. The above list is from a 1990s Quincy instruction manual and I believe there used to be a 230 model as well (which must have been out of production when this manual was printed).

Never saw a 2 stage compressor without intercooler piping. How would that work? Example?it's got two unloaders, which screams "two stages" to me, but I supposed it could just be two piston single stage. Intercoolers are sometimes optional,
how would it work? connect low pressure outlet to high pressure inlet, inside the head. or with a sandwich plate on the side of the heads. or cast it into the head on the side with the flywheel fan, for minimum effort "intercooling". For all I know there's a finned pipe out of frame on the unit pictured.Never saw a 2 stage compressor without intercooler piping. How would that work? Example?
Wow. Please post an example of a brand of compressor pump that's set up like that. I get the theory, never heard of or saw any compressor set up like that. So I'm curious if it's just that........theory.how would it work? connect low pressure outlet to high pressure inlet, inside the head. or with a sandwich plate on the side of the heads. or cast it into the head on the side with the flywheel fan, for minimum effort "intercooling". For all I know there's a finned pipe out of frame on the unit pictured.
You're gaming the thermal mass of the compressor. plenty of compressors are not rated 100% duty cycle because they don't have the thermal capacity. I don't like that either but it's done all the time, and even sold as 'normal operation.' I'm not endorsing it as best practice.
kinda like old-school turbo cars without intercoolers. might not be the "best" but it functions.
Quincy 390?
So I've decided I'm gonna pass on it and look for a 350. Thanks for all the replies.No. Its a single stage.










What motor and pulley size is that?Hopefully I can play along here, if mine doesnt count as vintage please feel free to delete my post. I picked up this quincy compressor for 500$, I was told it ran at the time of removal(pretty sure this was a lie).
I got it in my shop and cleaned it up, and started a thread on here looking for information on it(I knew what it was but wanted more information) like CFM at 7.5 HP instead of 10 etc. since the tank was from 1979 I decided id play it safe and pressure test the tank, only to find out it was cracked next to the foot. So I had to track down another tank and what a pain that was. I found this IR compressor for 250$ non running but the tank was from 1997 and it had an after cooler on it.
I removed everything off the tank, pressure tested it(it passed), then I mounted up my pump, and motor and then made the belt guard/aftercooler work with the quincy stuff.
not long after I had it up and running I had an oil leak develop from the bearing plate on the sheave side. So now it was time to take it all back apart to fix this leak. so now was a good time to repaint everything.
I got it all back to my shop and reassembled it.
I still had an airleak that I shoulda corrected before painting it but I fixed it afterwards and all was well. My wife was nice enough to use her cricut to print me a new quincy logo for the tank also.
last but not least I installed a solberg silencer
I woulda never got this compressor up and running if it wasnt for @The Tool Tyrant He reached out to me after my initial thread and was a guide/help the whole way through the process!! also I made a new friend !! I can say if it wasnt for him reaching out I probably woulda scrapped the compressor and just found a different one. the compressor is a 350-18 and it puts out more air than ill ever need!!
7.5HP and id have to look but I think the pulley is right at 7"What motor and pulley size is that?