Quincy 310 Problems/Possible Replacement

[OverkillYJ]

So my Quincy 310 ROC 22 is mounted on a 80 Gallon Tank with a 2HP 1250rpm motor. It runs hot, really hot if it doesnt get a chance to cool down. I am guessing something is wrong with the oil pump, but I cannot find any reliable info on how the oil pump is supposed to properly operate in the first place. I just rebuilt it. New race inserts, gaskets, valves, and piston rings.

If it runs say 20 min out of an hour it is fine like that all day. It is supposed to be continuous use 2stage. But now when I started media blasting with a 1/4" nozzle it started burning up on me and squeaking. The reason I rebuilt it was because of blown gaskets, but it ran fine. I am guessing things are getting so hot they started expanding from lack of lubrication? I dont think anything changed with the pump from what I rebuilt, I just never ran it like this before. I know in hte months before I rebuilt it it was getting warm enough from running a lot that it would heat the pipes and valve where I turn on my air lines that power my in ground lift and things. It is mounted over a bathroom so it is usually out of sight out of mind when it is working.

At this point I am thinking I need a newer pump to stick on top of this tank. Something that can run for hours without burning up on me. I am having a hard time finding anything I feel comfortable buying. I would like as many CFM as I could get without buying a new motor. So Whatever the best 2HP 1250 compressor is I should run? I have no idea.

I would fix and troubleshoot the oil pump if I could find detailed info about it before buying a new pump. Just taking it apaert though and figuring it out does not look like an option. It is a pretty complicated piece from the looks of it, and I do not know torque values or anything like that to properly reasemble it. I am guessing with the bearings and things in there I need to be pretty spot on or it will fail.

ANy help you guys could offer would be awesome. This forum always seems like a good place to start. I already have the schematics of the pump, and spoke with Quincy and two parts resellers. Apparently this Compressor built around 1962 does not have any real documentation for rebuilding, at least nothing for the public. They said the parts diagram whic is just bare bone schematics lacking even meqasurements of any parts is all there is. Because of that I did not mess with the oil pump at all when it was dissasembled. It is the only part I skipped. The pressure oil gauge is not reading anything at all no matter how much I adjust the screw in any direction etither.

I am doing my best to include any info you guys might need so I do not get answers like "go adjust the oil pressure". I have already spent hours playing with it from the outside. I do have all the O RIngs and things that came in the kit. if I knew how to safely take apart and inspect the oil pump for damage to repair I would do it. I am a technichian and this is actually easy to work on, but I know enough to know I need more info before I dive into the pump itself when I still have a pump that works fine light duty.

 

[bsaint]

Do you have a way to read the actual temperature? Maybe a laser pyrometer?

 

[A_Pmech]

Does the arrow at the top of the oil pump agree with the direction of rotation of the compressor flywheel? I think they had reversible oil pumps by then...

The pressure oil gauge is not reading anything at all no matter how much I adjust the screw in any direction etither.

You've been running this thing with no oil pressure? You might as well tear it down and overhaul it a second time at this point. Just like a car engine, these machines will NOT run without oil pressure.

 

[OverkillYJ]

Well it is turning in the proper direction. It is also getting oil to the valves. When I first put in back on the tank I did not have the head bolts tight enough and actually got some oil seepage, so I know I at least have some oil making it to the top. And it is the proper compressor oil I picked up at NAPA for too much money.

That is why I am so damn frustrated. I cannot figured out why it is squeeking when it gets hot. My best guess with these temps is the oil pump, especially since it is the only thing I did not rebuild. I hit it pretty heavy with some brake cleaner to make sure the pathways were clear and that was about it.

I want to buy a laser temp reader, but none of the cheap ones go up to the temps I want so I have been putting it off. To give you an idea of the temps, it will stay about as hot as you can tolerate holding your hands on if it runs 1/3 of the time. More than that and it is like a radiator in the dead of winter where it is not red hot or anything, but just a little too hot to hold your hand on it for more than a few seconds. Hope that helps give you an idea.

And no, I am not tearing it back down with the info I currently have. I have too much on my plate where I either need to use my lift, or my media blaster. At this point I am thinking of a bolt in replacment compatible with my motor unless someone has some good troubleshooting steps for this oil pump, and info on dissasembly. I can figure it out, but I do not have time for that.

I figured I would replace it if possible with just a compressor pump that will handle continuous use and the 135-140PSI I normally maintain. Then when I have time to get to it I will look at my current pump again. At that point I will determine if I will fix it and use it again, sell it, or part it out. Right now I just either need solid advice on a fix for this oil pump, or some reccomendations on a pump. I have been looking on Craigslist, but nothing within 100 miles of me seems worth picking up, or is way too expensive.

3 phase is an option for me since I have 300AMP service total on my property with two meters, but I do not want to spend the money unless it is like $400 for a used pump motor combo. I would also need to run the 3rd hot from my home's 200 amp service, into my shop which has the 100AMP service. I would do it if what I was buying was in excellent shape and put out 20 CFM or more though at a decent price of course. Maybe a pipe dream.

 

[A_Pmech]

Well it is turning in the proper direction. It is also getting oil to the valves. When I first put in back on the tank I did not have the head bolts tight enough and actually got some oil seepage, so I know I at least have some oil making it to the top.

That's not a good sign... It sounds like it's passing a lot of oil by the rings. There are no oil passages between the cylinder block and the compressor head. The valves do not require lubrication.

 

[scw1991]

1250 RPM motor? that doesn't sound right. I'm guessing 1725 RPM is the standard for this compressor. If you slow down the pump too much, you will not develop as much oil pressure. It's no different than a car engine. If you could somehow idle it at 100 rpm, it would self destruct due to lack of pressurized oil lubrication.

If you run a compressor non-stop, it'll get pretty damn hot. The discharge line to the tank can easily reach 350 degrees. So this means, the cylinder head/block will get very hot as well. Do you have this compressor shoved up against a wall by chance. You must have ample room to allow free air to pass through the flywheel across the compressor fins.

the Quincy guru's will need to chime in with respect to the oil pump itself and it's assembly tolerances. Perhaps the same as the Model 325 or of similar design?

 

[wild cowboy]

what type of oil and what viscosity are you using in it?

 

[MacMcMacmac]

Stick a 100psi pressure gauge in the intercooler relief valve port and see what pressure is in there. It's the 1/4" NPT valve sticking out of the top of the cylinder head nearest the flywheel. Should be around 40 psi. If it is way low, you have low pressure valve problems. If it is equal to the discharge pressure, you have high pressure valve problems. It should flicker a bit, but should not be dropping back down to near zero between strokes. If the unloader system is plumbed properly, you would not be able to pump air with low oil pressure.
Are the valve plates ring shaped or shaped like a coin? The coin shaped ones can sometimes wear their guides and then sit off-center, allowing a small crescent-shaped air passage even when the disc is seated. This will cause air to return to the cylinder to be re-compressed. Re-compression of air due to faulty valves is a guaranteed recipe for severe overheating.

Using automotive multigrade oils in a compressor will also lead to severe carbon build up in the heads, preventing proper valve movement and seating, leading to poor performance and overheating. This is especially true if the compressor is passing oil.

As was said, there should be no oil anywhere in the head or up past the base of the cylinder block.

 

[OverkillYJ]

Well I will check the prssure on the tip of the heads. I know exactly which ones you are talking about. The low pressure cylinder is where the heat started. Hopefully just a valve not seated properly, that would be nice. I did take my time with them with the head in a vice so I could work on it with things moving around, but I know it is still possible.

And no, I used strait 30 weight non detergent compressor oil, like I said, nice and pricey. From what I have found out though, the moisture from the air does not mix well at all with normal motor oil and will actually cause separation and breakdown of the oil resulting in that white **** I bet a few people have seen before.

So I will check the pressure, and if it is bad I will start with the low pressure valves and reseat them before buying the new crush washers just to see if it makes a difference. I know if that is the cause just reseating them without replacing the washers will make a noticible difference in the heat and tell me right there what the problem is.

I will update when I have the time to climb on top of my bathroom roof instead of working. Thanks for the valve advice. As for the unloaders, this one came with the bells and whistles, but someone removed part of the setup and switched to a more modern pressure control. The pressure goes to a gauge which controls a relay which powers the motor. Its standard pressure is set to 140PSI. I would have thought the pressure too high if it was not heating up well before it hit 100 PSI with an empty tank.

As for the oil I saw seeping, must have been heated assemblers lube running down the side of the compressor I saw. Once I tightened it down It completely stopped and probably just dumped any excess into the tank.