I'm looking to get a U.S. General Air Superiority 60 gal. 5 HP 165 PSI Two Stage Air Compressor. It does 16 scfm at 90 psi. It is second hand looks in good condition. 325 bucks. The motor burned out and was rewound professionally about a year back with good American components (not Chinese junk stock). Comes with HF driver and some hose and I think a paint gun. What do you think? Anything to look out for?
that should be a pretty good unit, it will need a 30 amp 240 volt circuit #10 wire. that will probably draw about 24 amps. the burned up motor was probably due to insufficient electrical connection. If it has been run after the repair without fixing the electrical problem, the new motor could have received some heat damage. If you can find out about the power supply that it was being used with it would be good. Art B
It is on a 240v circuit direct wired into the breaker. He said he bought it at an auction a few years back and the original motor stopped working, so he had it dissasembled and rebuilt including bushings and bearings and new copper wire wound. So from what I understand it should be essentially new. He was unsure of the amps off the top of his head but I'll have a look when I go see it today. Not sure I understand what you mean by electrical problem? Like a power supply or faulty connection you mean leading to the motor?
What i have seen in the past with the larger compressors is that they get wired to a 20 amp circuit with #12 wire. Unless the compressors are used hard they typically don't blow the breaker but the small wire causes a lower voltage and heat in the windings, it also causes a hard starting issue. 3 hp compressors run fine on a 20 amps circuit but in a lot of cases the need for heaver wiring etc. isn't observed for the 5 hp compressors. Art b
If you're running 240V just run #10AWG and save yourself the trouble. It doesn't cost that much more and you can sleep soundly at night knowing if your shop/house catches on fire it wasn't because you cheaped out on that cable run. Also when you bring that shiny (or dusty) new/new to you welder home you can plug in and not worry about it being too big for the run. (might have to switch out the breaker....but can't bat 100% all the time). CBB
Oh ok so you mean just rewire the power cord to the motor if it is 12 g. That's easy enough to do. I'm about to go in and look at it. The real challenge will be if I can tetris it into my Toyota Camry 2006 and get it home hahaha.
Here's a video of the compressor. 350 gets me the compressor, hose, HF air drier, and hose spool. Going to pick it up on Friday. Will take pics of it stuffed into my 4 door sedan car.
That's the identical compressor pump that was on my 80 gallon Sandborn Black Max, maybe smaller cylinders, but same after cooler, etc. I used it hard a lot of years, it was a good unit.
Perfect. I'm happy to buy it. Especially with the air drier and retractable spool included. I'm going to have trouble transporting it back to CT but I'll cross that bridge later. A pickup truck with two capacity would be fantastic...
I fixed up a very similar cast iron two cylinder compressor unit running off a three horsepower motor. It had a 1/2" thick cast iron reed valve body between the cylinder head and the cylinders that got rusty from atmospheric moisture and needed skimming off on a surface grinder and a new sheet steel reed valve to bring back to new condition. The only other problem I had was the pump slowing down when close to full, it really sounded like it was struggling even though the motor current was normal. The problem turned out to be a slightly loose belt and once tightened the problem went away.
Yeah my only concern is I think he didn't keep the tank drained. It was pressurized when I got there and when I left he made sure to let it top off and hold air. I wonder if that's how he's had it for the last 2 yrs? He says he's only used it for 2 or 3 hrs of run time since it was rebuilt. This compressor is cast iron too right? It's a 2 stroke.
I like to run a hydraulic hose out to a ball valve to drain. Condensate collects in the hose, which doesn't rust, the hose won't vibrate into, and getting the valve out from under the compressor makes it easier to drain so you drain it more often.
I'll see about getting some good hose for that. I normally drain after each use. Don't like water sitting in the tank. I think it takes 3/4" hose if I'm not mistaken.
I put a bronze street ell in the bottom of the tank and then adapt to a 1/2" hydraulic hose. Mine have been 3/8" drain with a 1/4" drain valve. I live on a farm so always have spare hose laying around. 3,000 psi hose is over rated for 165 psi air. I don't like water in the tank either, and I leave my compressor on full time. I like having the water settle into the hose or pipe.
I'm not sure they are one stage pumping into the next cylinder. I think it's just two cylinder to even out the load on the electric motor. Speaking of draining the condense: first day on the new job I notice the air compressor is running all the time, I drain the condense and get seven buckets of rusty brown water out of the tank. The boss bought a new compressor six months later as it was worn out.
Ya did good man. New one's are 8bills. https://www.harborfreight.com/5-hp-60-gallon-165-psi-two-stage-air-compressor-93274.html 2 stages compressors recover faster. Unless you are running a couple of DA sanders at once, you'll never hit the capacity of that pump.
If you buy it, pick up an automatic condensation drain valve to continuously drain the condensation. These valves activate the condensation drain at regular intervals to blow the water out. Connect it to a hose leading outside and you're set. You can buy those at Northern Tool, Harbor Freight, etc. for not too much money.
