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by Steven
(Menasha, WI USA)
So this was a “barn find” that I would like to use to do some painting and clear coating. However, there’s no shut off switch on this thing, and I don’t want the motor running constantly – it would get kind of annoying.
At any rate, here are some pictures I took of this beast of a compressor.


As you can see, it’s a 3 phase motor that runs at 208/220/440 volt (which I’ve never seen). It’s wired for 220, but the plug is missing.
I need to know what wire is what (red, black, and white). I’m assuming the white is ground and the red and black are the two hots. I would also like to retro fit a pressure shut off switch if it’s doable. Amp ratings are as follows-
208 volts – 14.6 amps
220 volts – 13.8 amps
440 volts – 6.8 amps
I’m going to have to buy a generator to power this (I converted my cheap storage unit into an insulated paint booth). Would an 8000 watt generator work? Or should I step it up to a 10 kw? Any help would be appreciated.
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Motor voltage
Is it 3-phase or tri-voltage? I think the latter.
If it’s 3-phase, then all three wires are “hot”. And there should be a green wire or ground point on the motor, somewhere.
If single phase, then yes, the white is neutral, red and black hot. And there still should be a ground point, somewhere.
Can you get a better shot of the motor plate? Can’t read a lot of it…
If it’s single phase, then 8KW *may* start it, but more likely the 10KW unit would be advised.
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And another thing…
I am not mechanically intelligent enough to understand how these older, continuous running compressors work (how they don’t overfill the air tank).
I do have an emglo gas air compressor. I might just mount the gas engine to the Newman compressor, switch the pulleys if possible, then run the gas engine at idle. Not sure how much work it would be, but definitely worth it in the end. I can’t use the gas compressor for painting as it develops way too much water in the air lines (I’m shooting moisture cured 2k Urethane). Any thoughts?
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Unloading; and water
I am not mechanically intelligent enough to understand how these older, continuous running compressors work (how they don’t overfill the air tank).
>> Three main ways – one is an automatic clutch, like on some motor bikes, not that I’ve actually seen that type on a compressor. Two is a fork that slides under the intake valve, holding it open so no compression takes place. That type is used on many air-brake pumps. Three is to just open sort of a three way valve to the atmosphere – one leg is from the compressor, and one just goes to ambient air, while the other goes to the tank.
<<
I do have an emglo gas air compressor. I might just mount the gas engine to the Newman compressor, switch the pulleys if possible, then run the gas engine at idle. Not sure how much work it would be, but definitely worth it in the end.
>> It’s doable, but then you say; <<
I can’t use the gas compressor for painting as it develops way too much water in the air lines (I’m shooting moisture cured 2k Urethane). Any thoughts?
>> Yes. A given amount of ambient air will generate the same amount of water, no matter what. Period. See:
Take that first link to learn about where the water comes from, then go back for what you can do about it.
HTH…
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Unloading and water
The reason I don’t use the gas air compressor is because although it is a 5 hp engine, is has just 2 “torpedo” tanks. I need 13 cfm at 30 psi for my guns. The little compressor head would have to run at full throttle to keep up, THAT is where my issue lies.
If I take the gas motor off and mount it with the Newman compressor head on my horizontal 60 gallon tank, and just run the gas motor at idle, I won’t have anywhere near the amount of friction heat to deal with, which when pumped into a much cooler air hose, creates condensation, and a lot of it from what I experienced last year just doing some bead blasting.
Does that make more sense?
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Water
Forgot to add that while bead blasting, I used 3 desiccant air dryers. 1 post gas air compressor to 60 gallon tank, 1 post 60 gallon tank, and the third one at the blasting unit inlet.
However, I had to crank the throttle all the way up to supply the air required. I can’t tell you how hot the copper supply line from the compressor head to the torpedo tanks was, and I just replaced the oil in it. Lastly, I coiled a 20 foot hose post 60 gallon tank into a giant rubbermaid container filled with ice. Still plenty of water built up inside my compressed blasting unit. Maybe I need a new compressor head?
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Yeah, that makes more sense.
But more sense, and easier, probably, would be to replace the pump on the emglo, and run the big tank in series with the wheelbarrow tanks.
How ’bout that?
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Never thought of that…
Worth a shot though. I’ll see if the bolt pattern matches, or if I need to do some drilling.
I had it set up that way but having to run that gas engine at full throttle wasn’t doing me any favors. It’s always something…
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Water
Steven, I just noticed I somehow missed your post regarding your de-watering technique.
I’d try getting a couple of water separators and use those right after the tank, and put the desiccant dryers in series right before your gun.
You might try getting some pipe, as opposed to hose, in your ice, or just run some vertical sections of pipe with drip legs.
There are a lot of DIY ideas for refrigerant dryers, too.
How long do you blast at one shot, and how much water do get, being surrounded by water?
(I just looked up where you live)
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It’s a Kellogg
This is a Kellogg pump, probably a 335 or maybe a 340. It should make about 17-18 cfm at 100 psi. You have a 3 phase motor there. It will not run off of 230v single phase.
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Water
Doug,
I tried blasting for 5 minutes at a time (gas motor was going full throttle, so I had the supply). However, after about 20 minutes I opened the top of the blasting unit and had to take an aluminum rod to break up the clumped up glass beads at the bottom of the unit (I was using fine grade at the time). If it gets hot in spring/summer, it normally is extremely humid, sometimes to the point I refuse to go outside. If I get even one drop of water in my 2k urethane paint, it’s pretty much game over, then start over.
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More on water
Yeah, I got a taste of that heat/humidity when I went to my daughter’s graduation from Great Lakes Navsta.
Anyway, short of a refrigerated dryer, more surface area (pipes or tanks – for heat dissipation) along with separators and desiccant and/or deliquescent dryers is what it’s gonna take.
Compressed Air Deliquescent Dryer
It’s gonna be a chore (and maybe expensive) to get to where you need to be on air treatment.
Keep us posted.
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Roger:
On re-inspection of Steven’s post, I guess it does say “phase 3”, but then a blue wire (or something other than white) must be missing? What say, Roger?
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3 phase
That’s what I was wondering. I’m not an electrician, so I am not sure how this motor was wired. Unless there is a separate ground, which I’m not sure that would even work.
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Power
If you don’t have a HEFTY 230v supply, forget running that Kellogg. It would be much easier to throw a 10hp gas engine on it and buy the proper control valve for it.
Then you can tackle the water problem.
Short of a twin tower desiccant dryer and proper filters, I don’t see how you are going to get the air dry enough. High quality compressed air is not cheap.
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Gas engine
I am going to mount my 5 hp gas air compressor motor with the Kellogg head. As far as the air drying technique, I plan on using twin automotive A/C condensers post compressor head in series with a couple of drain valves, then use high powered fans to keep them cool. Followed by a large desiccant air dryer. Then pipe the air to the tank. Plenty of junk yards around here.
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Twin condensers
By twin a/c condensers, do you mean in parallel?
Unless they have BIG tubes, you may get flow problems.
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Well this wasn’t part of the plan…
So I’m relocating my storage unit to a different site that’s closer to where I live. I picked up the 60 gallon horizontal tank, and there it was. The pressure shut off switch. There are two wires coming out of it (Black and Brown) with the ends cut off so again I have no idea how this is wired together.
So now I’m thinking if I use the gas motor for the compressor, I’m going to need some sort of spring loaded pressure relief valve plumbed in. The tank itself has 4 “outlets”, 2 of which are plugged. No need to blow up a nice air tank like that.
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Gas Motor
You MIGHT get by with an 8hp gas motor, but the 5hp motor will not be powerful enough for that pump.
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A/C condenser
Yeah you’re right. My output tube is 3/4″. They don’t make an A/C condenser with pipe that big. I am also debating making a “vertical radiator” out of 3/4″ piping with ball valve at the bottom. The pipe coming out of the compressor head would go through a metal box filled with ice.
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Gas Motor
I don’t get it. The electric motor is a 5 hp motor. Not sure why it wouldn’t work. I would think the gas motor would have a little more torque, but I’m not familiar with gas vs. electric motors either.
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Gas vs Electric
Never mind, a simple Google search answered the question. I’m probably going to do a little overkill and mount a 16 hp engine on it, just need to figure out the shaft diameter and length.
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Water
Hey Steven –
You probably already thought of this, but just in case not…
Depending on how dusty your work is, if you can figure a way to return the used, already dry air to the intake of the compressor, you’d have less water to remove than using outdoor air.
You might need some sort of air “settling tank” (think septic tank) to let the dust drop out, and maybe an A/C filter or two. Could be made of plywood or even cardboard, and some large pvc pipe or flex exhaust tube.
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Water
Yeah I could probably do that, but I’m a little short on space. I’m going to use schedule 40 pipe (around 50′) and build a water trap. My only concern right now is that I have the new gas engine and pulley, I need to know how to tighten the 2 belts (not sure what kind of deflection is acceptable with a compressor this huge). I’m thinking hydraulic jack and boards. PS: I looked at the pressure relief valve near the shutoff valve, it’s set for 200 psi?
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Sched 40 pipe
Please make sure that wherever you are using sched 40 PVC pipe for compressed air that it NEVER sees pressure. Sched 40 pressure capability degrades quickly when it is exposed to heat, and you may be building a serious problem in your air system.
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Schedule 40 pipe
I’d never use PVC. I’m using steel.
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Drive belt deflection
You probably know that that depends on the length and how hard you push on it. I think I’d start at maybe a half inch with finger pressure, and if it doesn’t slip, leave it. If it slips (either that way or after you tighten it some more) just make sure it doesn’t start to slip. If you get it to less than a quarter inch or so, I’d think it would probably be too hard on the bearings..
But then, how long is it going to be? I’m thinking less that a couple of feet? (center to center)
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Belt Tension
Yeah I tried bolting the motor down and “rolling” the belt over the pulley, and I’m still getting over an inch of deflection. I don’t want this to turn into a two person job. That’s why I was thinking of wedging a jack and some boards in between the two.
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Newman compressor belt tension
Oh, yeah. Sure, you can do that if you have places to push against that aren’t liable to break.
Or even just use wedges to get it where you want it, keeping the pulleys in line, of course.
Have fun.
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