Need help identifying Quincy Compressor
- Thread starter Ten4321
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94yj
Well-known member
i would say it is a quincy 325
norcalpablo
Member
It looks like it might be bigger than a 325. Google images of a 370 and see if it is similar. You could also check Quincy literature or a site like Mesa for dimensions:
http://www.mesaequipment.com/Html/Products/Quincy/qr25_basic.html
In any case, it's a great compressor!
http://www.mesaequipment.com/Html/Products/Quincy/qr25_basic.html
In any case, it's a great compressor!
TapperMan
Well-known member
Looks like it might be a 370. Compare to pictures here... http://www.ironplanet.com/for-sale/Air-Compressors-Quincy-370-Shop-Air-Oklahoma/404580
Grounded Ken
Well-known member
Could be a 340, 350, 370 or 390. All of those are 6 valve machines. Not a 325, that is a 4 valve. Without a nameplate your going to have to take off the head and measure the pistons.
Trey T
Well-known member
Definitely not a 325. It's like a 370 that will required 7-10HP motor. Highest HP single phase I've seen is 7.5HP.
When you run gas engine, it's about twice HP than electric motor.
When you run gas engine, it's about twice HP than electric motor.
Under no circumstance will I be removing the head off this thing. I'm looking to replace with a gas motor not electric. The Kohler was 23 hp but it put out that hp at 3600 rpm. Based on pulley size 3600rpm would spin the compressor well beyond it's 1000 rpm limit. I'm assuming the Kohler was being used at a lower rpm. I've tried comparing dimensions, however, I'm not sure if the oil filter should be included in the length measurement. I'm guessing that this is probably a 370
You don't have to remove the head to service the valves, and even if you did, it's a trivial procedure to check the piston tops and cylinder walls, well worth the cost of a gasket kit and/or head overhaul kit!
I'd also recommend draining all the oil while you're at it, and opening the inspection plate on the side. This will give you perfect visibility to inspect the high pressure piston wrist pin, check for end play on the crank, any kind of unusual bearing wear, and to clean the crank case of any accumulated junk/cruft. It's not a difficult procedure, and may potentially add years of life if you were to find, and subsequently remove, a potential hazard. The large nut on the front of the pump, at the very bottom under the oil filter/pump assembly, is actually the oil pump pick-up, with a screen on the back side. It's good practice to remove that as well and clean it out.
To remove the head, work over the valves, drain the oil and do a lower end inspection is probably not more than 4 hours of work. The easiest way to break those valve covers loose with a slot in them, or the valve hold downs, is a long piece of 3/8" flat bar steel after letting some penetrant soak the edges. A large pipe wrench will easily remove the unloader towers without making a mess of things. The rest is just a little bit of mechanic work, but nothing at all difficult.
Oh, and just for the other poster, 10HP single phase motors exist, but be prepared to pay!
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Grounded Ken
Well-known member
Without an ID plate how in the world did you figure out it is a 370?
340 27" x 16" x 30" length, width, height
350 28" x 16" x 31"
370 28" x 16" x 31"
Bore and stroke
340 5-1/4 - 3 x 3.5
350 6 - 3-1/4 x 3.5
370 7-1/2 - 4 x 4
Horsepower ratings
340 5-10 Hp.
350 5-10 Hp.
370 7.5-10 Hp.
All of the above are listed at 480 lbs. shipping weight.
They are within an inch of each other and they way the same!
If external dimensions are bigger than the above it is a 390, but the 390 is a whopper of a 2 cylinder machine @ 660 lbs.
If you go to order parts for this you only have a one in three chance of getting the right parts.
The only way you are going to find out the machine model without a ID plate is to get the piston diameters. The only way to do that is take the head off.
Not trying to be a hard ***, but you wanted to know what you have.
340 27" x 16" x 30" length, width, height
350 28" x 16" x 31"
370 28" x 16" x 31"
Bore and stroke
340 5-1/4 - 3 x 3.5
350 6 - 3-1/4 x 3.5
370 7-1/2 - 4 x 4
Horsepower ratings
340 5-10 Hp.
350 5-10 Hp.
370 7.5-10 Hp.
All of the above are listed at 480 lbs. shipping weight.
They are within an inch of each other and they way the same!
If external dimensions are bigger than the above it is a 390, but the 390 is a whopper of a 2 cylinder machine @ 660 lbs.
If you go to order parts for this you only have a one in three chance of getting the right parts.
The only way you are going to find out the machine model without a ID plate is to get the piston diameters. The only way to do that is take the head off.
Not trying to be a hard ***, but you wanted to know what you have.
Yet another reason to remove the head! Sometimes the ROC is stamped into the front of the crank as well. If there's an obscure ROC on one that isn't ont he other, that might help, but it's far, far easier to simply measure the piston diameters - 100% concur, and it's in the line of good maintenance anyway.
Grounded Ken
Well-known member
And it's easier than any car engine!
Agree with the 370 or possibly 390 based on the number of valves, belts and inter cooler pipes. Just pull one of the side plates on the block and measure the crank. Or measure the crank shaft where the pulley is. Quincy should be able to tell you from that.
Has it been out of service long? What is the story behind it? If it has been sitting long it would be a good idea to pull the valve packs and check for rust. They are pretty common for rusting if setting. I have a 270 now (upgraded from a 230) and both needed the valve packs cleaned. BTW, congrats on getting a 2 stage version. I would like to find one, but my luck seems to only find the single stage ones.
Has it been out of service long? What is the story behind it? If it has been sitting long it would be a good idea to pull the valve packs and check for rust. They are pretty common for rusting if setting. I have a 270 now (upgraded from a 230) and both needed the valve packs cleaned. BTW, congrats on getting a 2 stage version. I would like to find one, but my luck seems to only find the single stage ones.
I doubt it's a 390, the crank case part number (6904) isn't correct. That crank case is a dead match for a 340, 350, or 370. Later model 340s and 370s used a 6904R (Revised?).
Has it been out of service long? What is the story behind it? If it has been sitting long it would be a good idea to pull the valve packs and check for rust. They are pretty common for rusting if setting. I have a 270 now (upgraded from a 230) and both needed the valve packs cleaned. BTW, congrats on getting a 2 stage version. I would like to find one, but my luck seems to only find the single stage ones.
My complaints about having a 270 would be limited, especially if it was upgraded to the newer piston rings. That's a beast!
Oooo..... Good catch. So maybe a 370? I am really surprised it doesn't have a riveted tag on it.
My complaints about having a 270 would be limited, especially if it was upgraded to the newer piston rings. That's a beast!
It's a mid 80's model IIRC, don't remember the ROC off hand. O yes it is a super smooth beast, but the 100psi max is kind of a pain as it cycles on (~75psi) and off (~105psi) quite a bit. It was a good upgrade from the model 230 I had. That pump was a real PITA, super difficult to find info on. Basically it was an older version of the 240. Of course when I searched google for "Quincy 230" it came up with 230 VOLT quincy compressors not model 230.
The only thing I did to the 270 I have was to put a "soft" rebuilt kit in it, basically all head gaskets. When I picked it up at the local dealer they gave me this real funny look ( I was ~19 at the time). Like O.. are you fixing something at work? I told them no, it was just for my home garage, I hope it is enough to fill tires and the occasional basket ball. The look on their faces was priceless.
I have less into that pump, a really goofy single phase 10hp motor and two 60 gallon tanks than the average ~$400 60gal cheapo goes for.
I don't really NEED the higher pressure of the two stage, but it would be nice to be able to leave the compressor off for a longer period of time. Quincy pumps are designed to be operated at a specific duty cycle to keep condensation out of the head. This is where rusty disk valves come in. But it is funny to see the look on people's face when the see it for the first time. It sits on the floor in the corner connected to a 60 gal vertical above it as well as another 60 tank up in the attic. So quite, so smooth, just a chug, chug, chug. I think the unloaders make a pretty sweet sound while in operation.
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I don't know it's a 370 I said I thought is was a 370. Which was an opinion I based on the engine that was powering it. I am not intimidated by the process of removing the head its just that I've taken apart enough motors to know that the cost of replacement parts always tends to outweigh the cost of just buying a used working unit. Someone posted a picture of a 370 with an electric motor and a 200 gal tank that sold for only $200. If taking this thing apart is what I have to do to find out what it is then it's not worth even bothering with.
Thanks for your help
Thanks for your help
I'll give you $200 sight-unseen (minus the photos at the top of this thread) for that pump, and I'll find it a great home.
Oooo..... Good catch. So maybe a 370? I am really surprised it doesn't have a riveted tag on it.
Some of the later models use a two-sided tape, perhaps an epoxy. I have a brand new QT-7.5 pump that is about to go into personal service that looks that way. Completely off-topic, I'm torn as to whether to put that one into service or rebuild the 325 ROC 7 I have that's still in fantastic condition (Nov 12, 1959). It doesn't really need anything, but I was going to put new rings, bearings and gaskets in it. Tough call.. I really like the 325 better, but the QT-7.5 has a higher output, is built almost as well, save for the aluminum head and lack of pressure lubrication. The bearings, crank, rods, and pistons are all just as good, given it's a splash-lub design. It has an aluminum head with stainless reed valves, which is good and bad. Slightly noisier, though arguably more efficient. Swapping a valve plate and gaskets is literally a 15 minute affair compared to rebuilding the concentric ring valves, which while easy to do, is nothing short of an hour to do correctly and requires significantly more parts.
OR, alternately, I'm almost finished with a newer model 240, which rivals the QT-7.5 in volumetric flow, but not peak pressure. These later-model 240s can easily turn 135 PSI.
It's a mid 80's model IIRC, don't remember the ROC off hand. O yes it is a super smooth beast, but the 100psi max is kind of a pain as it cycles on (~75psi) and off (~105psi) quite a bit. It was a good upgrade from the model 230 I had. That pump was a real PITA, super difficult to find info on. Basically it was an older version of the 240. Of course when I searched google for "Quincy 230" it came up with 230 VOLT quincy compressors not model 230.
It might be worth snagging those updated rings and measuring the current draw on your motor with a higher pressure switch, perhaps a cut-out of 125 psi just to test. If you see a linear increase in pressure up to that point, and don't see the motor drawing way more current and/or taking too much time to get there, I doubt the compressor would notice the difference based on the fact that its internals are exactly the same as its 2-stage brethren.
The only thing I did to the 270 I have was to put a "soft" rebuilt kit in it, basically all head gaskets. When I picked it up at the local dealer they gave me this real funny look ( I was ~19 at the time). Like O.. are you fixing something at work? I told them no, it was just for my home garage, I hope it is enough to fill tires and the occasional basket ball. The look on their faces was priceless.
I have less into that pump, a really goofy single phase 10hp motor and two 60 gallon tanks than the average ~$400 60gal cheapo goes for.
I don't really NEED the higher pressure of the two stage, but it would be nice to be able to leave the compressor off for a longer period of time. Quincy pumps are designed to be operated at a specific duty cycle to keep condensation out of the head. This is where rusty disk valves come in. But it is funny to see the look on people's face when the see it for the first time. It sits on the floor in the corner connected to a 60 gal vertical above it as well as another 60 tank up in the attic. So quite, so smooth, just a chug, chug, chug. I think the unloaders make a pretty sweet sound while in operation.
Yeah, I'm almost tempted to keep my eyes open for one of these 370s and just run it really slowly (~500 RPM) with a 7.5HP motor. I'd have to find a horizontal tank to mount it on, as the mass of a 370 would likely overwhelm the 80 gallon tank I currently use, or make it so top heavy that moving it would require a small crane or partial disassembly of the pump.
Maybe I've got a shot at this 370.. =D