Anyone ever look inside an air compressor pump?

Here's the deal. I recently scored a two-cylinder Wayne air compressor pump on Ebay to replace a Campbell-Housefeld pump. This was a lot cheaper than a replacement C-H pump, and is in good condition, having had only limited garage use over the years. It did not come with a flywheel, but the remains of the C-H pump has one. The only problem is that the seller of the Wayne pump says that the original flywheel turned in the opposite direction to the C-H (and every other compressor pump I've looked at this evening on Ebay). This is an old, but very high quality, industrial pump from the 60's. I can find no trace of Wayne any more to ask. I don't think it's the same company as Wayne water pumps.

This is a small cast iron pump, very similar in size to most 1-3 hp compressor pumps. It has poppet valves, not reed valves. I doubt very seriously that it has an oil pump inside. The only reason I can think of that it might not be good to turn it the wrong way is if there were an oil slinger, or some oil pickup on the con rods or crank to direct oil, and this might not work right if turning in the opposite way to the design. One other possibility might be labyrith oil seals, but the only seal visible looks like an ordinary lip seal.

Can anyone think of a reason why this couldn't be turned CCW instead of CW? Has anyone ever been inside a pump like this? Anyone actually know for sure?

Reply to
Bob Chilcoat
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My little Gardner-Denver has no exterior indication, nor could I see anything internally. If you do see a slinger of some sort, I would run it so the concave side leads. No seals on mine, just collector grooves with drain holes - could be why the crankcase was half full of water, still a good deal for three bucks. Gerry :-)} London, Canada

Reply to
Gerald Miller

Often times the pulley has the fan built into the spokes. If it turns the wrong way it will not blow cold air on the compressor cylinder cooling fins. Other than an oil pump that's the only reason I can think of. Is it possible to look around the inside with a dental mirror through the oil drain?

Richard W.

Reply to
Richard W.

I've never worked on a compressor, but remember hearing like you say that some had/have oil 'dippers' on the end of the connecting rod/s that are allowed to splash through the surface of the oil, and scoop up the same. If this is the case, I don't think they would work at all going backwards...

Erik

Reply to
Erik

Really depends on the internals of the pump.

If it is a splash lube, direction probably doesn't matter (I have several G-D's, some righty and some lefty G-D drie pulleys, otherwise identical) but you do want to look inside to be sure. Look for oil weep holes for oil to get IN to the bearings, as well as fins or plates to control the splash.

If it is pressure lube, it depends on the oil pump (some work either way, most don't) and the lube port configuration (some lube much better in one direction than the other)

If this is a two cyl, single stage, I will bet on splash lube and either direction is fine. Two stage, even splash lube, are often finiky because of the assymetry in the bottom end and the cylinders.

BTW: are the valves not 'disk' valves, not poppets? Poppets are real rare in compressors. (poppets have a stem through a guide to pull into place, disk valves are a disk in a cage with a light spring that push into place) If disks, pull them and clean them periodically, as any crud will cause them to hold open, and they will cook, as well as work into the cyl and eat the walls and rings. Excessive oil in the cylinder may ignite under compression as the unit warms, and will certainly coke up the rings and valves.

Reply to
e

That's not any problem unless the flywheel has a fan built into it and that can be overcome by putting a fan to the cylinders or providing ducting so that the fan sucks the air from around the fins of the cylinders. The motor you use can sometimes be made to run in the other direction and this is what I'd do. Poppet valves need to have a cam to work and that is kind of rare as this is an additional huge cost for anybody making pumps.

-- Why isn't there an Ozone Hole at the NORTH Pole?

Reply to
Bob May

One thing to check for, is if your compressors pully has a cooling fan built in as the spokes. I rather suspect that if run the wrong way..It will not cool properly.

Gunner

"I mean, when's the last time you heard of a college where the Young Republicans staged a "Sit In" to close down the Humanities building? On the flip side, how many sit in's were staged to close the ROTC building back in the '60's? Liberals stage protests, do civil disobedience, etc. Conservatives talk politely and try to work out a solution to problems through discourse until they believe that talking won't work... they they go home and open the gun cabinets. Pray things never get to the point where the conservatives decide that "civil disobedience" is the next step, because that's a very short route to "voting from the rooftops" Jeffrey Swartz, Misc.Survivalism

Reply to
Gunner

Thanks for all the good advice. Both the Wayne and my C-H flywheels have fan blades cast in. They're just opposite directions. The whole problem is rapidly becoming moot, as I discovered this afternoon when I took the flywheel off the C-H that it has a 3/4" shaft, while the Wayne pump has a 1" shaft. The C-H flywheel is too big to swing on my Myford, so I was thinking about how to center it accurately on the mill and bore out the hole. Then, of course, I'd still have to broach a new keyway. Lots of work, but of course that's what's fun about this sort of project.

However, just to check, I contacted the seller and he still has the original Wayne flywheel and will give it to me along with the motor pulley if I pay shipping. No problem, except now the motor will run in the wrong direction. It's not reversible, at least not officially (a '70's vintage Doerr 17.5 amp

1 hp). I can run the compressor backwards as we'd already been discussing, but now the cooling air will be in the wrong direction too. I'd already thought about ducting the air around the pump, so that the fan pulls air past it, but that's a lot of work too. Right now, I'd rather investigate reversing the motor.

What are the thoughts from the group about taking it apart, removing the stator and windings from the case, and putting them back in the other way? That will reverse the motor, but what problems, besides having to lengthen or shorten a few leads, am I likely to run into?

-- Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love America

Reply to
Bob Chilcoat

I think all need to find the start windings and flip them.

Reply to
Charles A. Sherwood

If it's an induction motor it should be much easier than that.

1: If it's three phase then just swap two power leads. 2: If it's a single phase then wait for someone else on the group to say how to do it (you need to reverse the phase of either the start winding or the run winding, but I've never messed with reversing single-phase motors). 3: If none of the above, and it were me, I'd trade the motor for a reversible one, or one that already runs the "right" direction.
Reply to
Tim Wescott

Waynes were good compressors. I think they merged with Dresser. I must have 25 compressors. None of them turn CW.

Reply to
Andy Asberry

Since the motor you are powering it with will turn in either direction, why don't you turn it the way it is supposed to turn. Leigh At MarMachine

Reply to
Leigh Knudson

Seems appropriate to ask on this thread.......I'm considering taking apart my CH 30 gal, direct drive, rated 4 HP (not a chance) Emerson motor........I hate the direct drive and was thinking it might be cost effective to get another pump and mount is and the motor seperately from the tank and use it as a stationary air supply for the shop.......the tank is, what $100? The motor, $200? I paid only $300 for the thing........Is this feasable or should I sell it and buy a HF belt drive or something??

Thanks,

Michael

Reply to
Michael

I believe there's some question as to whether the direction he was told it turns it actually the direction it should turn, or if the person who told him that either remembered wrong, or had it up running backwards.

?? The thing is obviously going to be designed to run at the motor speed. What possible improvement could you expect from separating the direct drive and running pulleys? If you run it the speed it's designed to run at, the pulleys are the same size. If you run it with a smaller motor pulley, the output is reduced. In either case you'll be introducing a side loading that the bearings may not be set up to take. None of which makes HF any better quality...

Reply to
Ecnerwal

On Tue, 30 Nov 2004 19:16:51 -0800, "Michael" vaguely proposed a theory ......and in reply I say!:

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Why exactly do you "hate the direct drive"?

Reply to
Old Nick

On Wed, 01 Dec 2004 03:36:18 GMT, Ecnerwal vaguely proposed a theory ......and in reply I say!:

remove ns from my header address to reply via email

The guy did say he would get another pump. If you bought a pump only that was deisgned to run at lower speed (belt drives usually are), the biggest advantage would be quieter running.

Reply to
Old Nick

Noisy as my ex-wife at full throttle. hate the noise. It's a good motor, but the pumps a tiny thing hung on the end. Takes a long time to fill the tank.......My thinking was to get a REAL pump (Quincy or such), and mount it on a stand next to the tank. Why? Because the stand on top is too small to mount much and would be top heavy. A bit of copper tubing should connect them ok, right? So, I figure the Emerson is a better motor than most, the tank is adequate, and with a belt drive, I could reduce the speed of the pump to recommended rpm's........My thinking skewed or is this doable?

Reply to
Michael

On Wed, 1 Dec 2004 00:40:54 -0800, "Michael" vaguely proposed a theory ......and in reply I say!:

remove ns from my header address to reply via email

In 3 words..buy another comp. If you want air buy another comp. If you then want to experiment with a spare air supply, start experimenting. But the if it's only a spare, the noise may not matter.

On the other hand you might that sort of lucky bastard that sell stuff. :-<

It does not matter how good the motor is. If that motor was designed to run that pump (and they rarely give you more), then you will not fill the tank faster by using a bigger pump. You have to match not only speed but motor power to the requirement of the pump.

It will be quieter, both because it's cycling slower, and because everything happens inside at a more leisurely pace. Less clatter and bang. You get a wupwupwup instead of Burrrrrrrrr!

IIRC, you get _about_ 2.5-3 CFM @ 90 PSI per motor _true_ horsepower. This would equate _roughly_ to maybe 2-2.5 CFM @ 120 PSI, where the pump cuts out. There are many motors around that have a BS HP rating.

IIRC you do not trust the HP rating of the motor you have. Sounds true.

What you can do, if the pump is too big for the motor, is slow the pump down, even below its design speed, using belts, to the point where the motor does not stall because (or before) the pressure gets to the max. This will take the same time to fill the tank as before you had the new pump, (but more quietly) if the original motor and pump were matched at all, and will provide only so much air for continued use.

However, there comes a stage where if you slow it down too much, the pump _may_ (depends on design) not be getting enough cooling air or oil, and this will damage the pump. You would need to find the lowest speed for any pump, and proceed accordingly. But remember, you can't simply make it go that speed if the motor simply won't. So proceed accordingly means do not use that motor if it cannot drive the pump at its required minimum speed at full 120 PSI /8 bar pressure. Add 10% for good measure.

Because there are many factors in the setup (pump efficiency, motor torque vs HP etc), you are in for some experimentation, unless you are willing to let the motor "loaf" and easily drive a pump that is small enough to stay above its minimum speed. This assumes that the motor is able to deliver enough power to give you all the air you want, and more.

You may also find that those direct coupled units are a bugger to separate in a way that allows the motor to be any use.

Not sure about the copper tubing. There could be vibration problems there. Best to use an armoured flex airline, I would think. You also have to make sure you have all the unloaders, pressure switches etc correct on the pump itself. But yes, basically from the pump unit, properly set up, you need a line to the tank.

Reply to
Old Nick

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