Hey guys, I'm new to the forum and already I have found a ton of useful information on here. I need some help identifying a compressor that was left on a property my mom bought and if its worth rebuilding, I think it might be an old Quincy but thats just a guess. It's been sitting outside in the weather for who knows how long, there was a tarp covering it but it has a big hole in the top so it hasn't been protecting it very much. I can't find a spec plate on the compressor but there is one on the motor and on the tank but the stank on the tank is not very readable, I'm gonna try to clean it up tomorrow to see if I can make anything out on it. The one thing I can read on the tank label is 250 gal (its a big sucker). Thanks for any help you can give.
Need Help Identifying Compressor
- Thread starter NIK640
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GeorgiaHybrid
Well-known member
I agree with it being an old Quincy QR-25 series but it more than likely is a 350 or a 370 compressor. The 350 can use a 5 HP to a 15 HP motor and the 370 comes with a 7.5 HP to 15 HP motor.
It could possibly be as large as a 390 but they can take a 7.5 HP to 20 HP motor.
The weight (if you can find a way to get the compressor only on a scale) is around 470 pounds on the 350 and 370 and about 650 pounds on the 390.
I missed the 200 gallon tank size I guess I shouldn't post at 3:00am. Yes it is not as small as a 325 measure the height to the top of the fins on the head and I will measure my 390 to compare.
William....
rwhite692
Well-known member
The pump will surely be worth rebuilding or possibly selling in order to get a smaller pump, since you are getting it for free.
Before you invest too much time in the rest of it though...you should first pull one of the tank plugs and take a look inside the tank to see how rusty it is (or isn't). That compressor does not exactly appear to have led a life of leisure.
Before you invest too much time in the rest of it though...you should first pull one of the tank plugs and take a look inside the tank to see how rusty it is (or isn't). That compressor does not exactly appear to have led a life of leisure.
No it sure hasn't. I was going to pull it all apart and have the tank tested before I even thought about using it. I would like to use it in our barn that I'm turning into a shop, would I be better off replacing the 3 phase electric motor with a 1 or 2 phase?
Charles (in GA)
Well-known member
No such animal as 2 phase (well there is, but I can assure you, you don't have it available to you).
If you have 3 phase in the barn, you are in luck and should stick with it. If you don't, you will have no choice but to change the motor. Whatever motor you chose, will require the right size pulley to make the pump turn at the right speed and the motor to draw the correct amps (not overload or loafing). This either hit and miss or possibly Quincy can tell you the combination you need for a specific motor HP.
7.5 hp is about as large as is practical on single phase. They do make 10 hp single phase, but not very common, pricey, and draw lots of current. As it is, you probably will need a 50 amp breaker on a 7.5 hp to keep it from blowing on startup.
Charles
rwhite692
Well-known member
The problem will be finding a reasonably priced single phase motor big enough to drive that 390, which as GeorgiaHybrid noted, needs at least a 7.5 (True 7.5HP).
if you call your power company they'll tell you if you have 3 phase available in your area. I'm guessing you dont, usually its reserved for down town/industrial areas.
What are you doing in this shop? If its just for personal projects and for servicing farm equipment you might want to consider simply scraping that and looking elsewhere as opposed to:
lifting and loading the tank then hauling it where ever to get it hydrotested. This is not as easy as it sounds, especially in the sticks as not many places offer hydrotesting services.
tearing apart and cleaning the entire pump which could end up being very costly, if not in parts then at least in man hours. Ideally you'd want to blast it to remove the corrosion which means you'd want a compressor to fix your compressor
. Also probably water in the case which isnt a huge deal but not good either. At the very least you'd want a new air filter, valve rebuild kit, complete gasket kit, and i'd probably would do the rings as well.and lastly, if you dont have 3 phase, you'll need to locate and purchase a suitable single phase which, new, by itself can run you around $500.
GeorgiaHybrid
Well-known member
These Quincy's are pretty bullet proof and before you do anything else, check the oil in the crankcase. If it looks good, make sure the pump turns freely. If it does, pull a plug and take a look in the tank with a scope. If you don't have one, see if a local tech or buddy has one you can borrow. The inside of the tank will be rusted (they all are...) but you need to make sure the tank is sound and not extremely pitted inside.
If all of that checks out, I would take it to a compressor repair center near you and have them check the pump to see if it was OK. The local ones around here will charge you $50 or so to hook up a motor and test run it. If it does not check out at this point, they might be willing to buy it for parts. If not you are not out much at this stage.
If it does OK, invest in a new pulley and a 7.5 HP single phase motor to run it. That compressor will give you a ton of air, run at a super slow rpm and be very quiet while operating. If you do get it running, you will discover why so many of us are Quincy fans.
Good luck...
If all of that checks out, I would take it to a compressor repair center near you and have them check the pump to see if it was OK. The local ones around here will charge you $50 or so to hook up a motor and test run it. If it does not check out at this point, they might be willing to buy it for parts. If not you are not out much at this stage.
If it does OK, invest in a new pulley and a 7.5 HP single phase motor to run it. That compressor will give you a ton of air, run at a super slow rpm and be very quiet while operating. If you do get it running, you will discover why so many of us are Quincy fans.
Good luck...
The documentation I have with my 390 says a 10hp is the min to turn it. If you don't turn it fast enough you will burn it up ( not enough oil through the oil pump) I do know I guy that is running one with a very large VFD on single phase and a 15hp motor. Seems to work ok for him. You can dump $500-1000 (or more) into parts for a rebuild very fast on a 390 pump. Check out my build link for pictures of my 390 rebuild. They are a BEAST of a pump!
William....
William....
If the pumps good keep it, look for a new receiver tank if in doubt.
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GeorgiaHybrid
Well-known member
William,
I will not be back at home until the middle of next week (in Florida for a convention) but the documentation that I have shows a 7.5 HP option from Quincy. It might be worth a call to them by the OP to see if it can be run on a motor that small. Another option with it being in his barn for part time use would be to set it up for continuous running with a gas engine to power it.
By doing that he can crank the engine, run it when he needs the compressor and then shut it off. Might be an option if he wants to run this unit. If he does not have a GOOD electrical service to the barn, a gas engine option is a cheap alternative to rewiring or running new service.
I have a friend that has been known to put his gas powered compressor on a trailer and take it out to a field to run his air jacks, air wrenches and the like while working on equipment that has broken down. Sure beats turning those ¾ drive ratchets.
David
Thanks for all the help guys, I really appreciate all the advice and suggestions from everyone. I'm gonna use the shop mainly for my cars and bikes as well as servicing equipment around the house. We live on 20 acres in the Santa Cruz mountains so there's always something that needs to worked on and I'm looking to build a pre-runner/ trophy truck in the future.
I checked the oil and it looks like it had been changed before they left it because its in great condition. After I figure out the electrical in barn I'm going to call Quincy tomorrow to see what they say about an alternate motor. I may have 3 phase up here because a few years back we installed an industrial generator to power our houses in the winter cause we get a lot of trees falling across power lines and I remember we had to change out our main panel but I don't know much about electrical either so who knows. Thanks again everyone for all the help, I'm glad I found this forum
I checked the oil and it looks like it had been changed before they left it because its in great condition. After I figure out the electrical in barn I'm going to call Quincy tomorrow to see what they say about an alternate motor. I may have 3 phase up here because a few years back we installed an industrial generator to power our houses in the winter cause we get a lot of trees falling across power lines and I remember we had to change out our main panel but I don't know much about electrical either so who knows. Thanks again everyone for all the help, I'm glad I found this forum
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If you like rebuilding/fixing projects and if its free more power to you however that compressor is MASSIVE overkill for everything you just listed. A unit like that would be used to supply air for a multi-bay garage with numerous mechanics. At the very least you'll certainly have bragging rights.
You could always sell it to someone on the GJ
It looks like your correct, they (Quincy) are listing the model 390 as min 7.5hp and a min rpm of 400. I have never run mine that slow, I guess I should try it... At that RPM the Baldor motor VFD whine is going to be louder than the pump!
At 7.5 Hp I would have to really question the logic of running that pump (650lbs+ of pump, hell the flywheel must weigh at least 200 lbs!). The efficiency can't be good, and the cost VS the benefit is off the scale. Run hard (full RPM 10-12 hours a day 364 a year) that pump can last upwards of 20 years, so at the lower RPM what 30 years?? The higher up font cost and the added operational costs to spin that monster for so little air just don't seem to make sense.
Now of course in the case of the original poster it might make good sense. His cost of acquisition is low enough ( FREE!!). If he can get a good single phase motor/starter/pulley for $500 he may be ahead of the game. This is assuming that there is nothing else wrong with the machine ( that pump could be an easy 30-50 years old as they have had the oil filter on them for at least 20 years).
The gas engine is also an interesting idea. To spin it at the low RPM will probably require a 16-18hp motor and for the mid range RPM a 24-26hp or full RPM 30+ hp. The gas option with a larger motor would allow him to run a much larger sandblaster ( the reason I have my 390
and also turn it down for general use.William...