I bought a very old Air Compressor, Thoughts?

[badpeanut]

I bought this old Curtis Pneumatic Machinery Company air compressor today for $50. It has roughly a 60gallon tank but a 110V motor so I doubt the CFM is very impressive. It works, but leaks oil (and I haven't figured out where). The tag on the pump mentions 1915, 1916, and 1921 patents but I doubt it is that old.

Unloading it from my pickup is going to be a chore--did I do okay with this purchase?

Is anybody familiar with these or know where I can get more information?

[cdowns]

an engine hoist and a couple of straps are how i move heavy stuff

i'd try to google for a dealer orinfo you may get off lucky with a set of rings seals and a hone job

[71swb4x4]

If you do the engine hoist I would back the truck into the garage, lift the compressor, and pull the truck out from under it. That way you don't have to roll the hoist with that big air compressor on it.
Do you have a barn at your place? You could use a chain hoist from a beam and do the same thing.

[msgross]

not as old as mine...




works great.. good but i'd say. find or make some new seals and run it. The motor might be a dual 110v/220v if you investigate it a little further. I wired mine for 220v and paid $200... 80 gallon

[Bus Ted Knuckle]

What a neat old machine. Grainger will have rings and bearings for it if you need them. You'll have to order them by size. Kinda looks like it is leaking from the front crank seal, but can't really tell from the photo. I don't know the rpm of your motor, or the rpm requirements of the pump, but a bigger pulley on the motor, or a smaller pulley on the compressor will get you more CFM. Is there a plate on the compressor or motor that has the rpm info listed? Can't pump a whole lot of air with a 110 motor like that though, but you probably could pick up a decent 220v motor if you kept an eye on craigslist.

I love old machinery, the compressor in my shop is a Vietnam era Air Force surplus unit that I took a gas engine off of and mounted a 220v motor. Mine puts 15CFM easy at 175 PSI.

[badpeanut]

I cleaned the oil off the motor nameplate today and discovered it can be hooked up to either 110V or 220V, so I'll go 220V. The motor is rated at 1750rpm, has a 4" diameter pulley, the pump has a 16.5" diameter pulley, so if my math is correct the pump is spinning at 424rpm (which is greater than the 160rpm minimum on the pump nameplate).

I'll check into pump oil seals. Do I need to worry about any type of air seals?

I've got an engine hoist lined up for next weekend to unload this thing.

[RichardJ]

If you are like me you won't be able to wait a week. When I bought my 5HP 80 gal vertical compressor years ago, I didn't have a hoist and in fact it was sitting on a pallet in the back of a friends truck. I unbolted the motor and compressor and manhandled them off the tank and off the truck bed. It's a real 5 HP compressor with 18 cfm @180 and not one of those fake 5's they sell today.

It'll be easier to clean the tank off as well.

Other than any tubing leaks or the valves in the head leaking, it may have a centrifugal unloader. If there is one or two small tubes from the head to the crankcase, near the end of the crankshaft, you will hear air escaping for a second or so when the compressor shuts down. This takes the pressure off the top of the pistons so the motor has an easier time starting back up.

If you change pulleys, you should reduce the cut-out pressure. Do remember it is an old compressor with a splash oil system. There is a dipper on the bottom of the connecting rods like the really old Stovebolt engines.

[badpeanut]

I got this pig unloaded (borrowed engine hoist worked well) and wrestled into the back corner of my garage. PO was complaining about poor results with his plasma cutter and painting--no wonder with the two ice cream pails of water I drained out of the tank!

Next up: 220V conversion

[truckdude239]

thats why we drain ours every night at work

[msgross]

I should drain mine...

[71swb4x4]

Sounds great. It's amazing what a small amount of maintenance can do to get a marginal piece of equipment turned back into a real workhorse.

[steppside69]

Nice find! You get it runnin yet?

[badpeanut]

I finished the conversion to 220V. It is hard to tell in this picture, but it is running. For the 60gallon tank it requires:

• 0 psi = 0 minutes
• 40 psi = 5 minutes
• 90 psi = 12.5 minutes
• 120 psi = 17 minutes
• 160 psi = 23.5 minutes

I don't have any air tools yet to estimate CFM.

I'd guess this pump is a single cylinder two stage based on the single air filter and smaller unit to the left?

The pressure switch currently kicks off at 160psi and kicks in at 90psi. 90psi seems low to me--I'll look into adjusting it.

This compressor is really quiet (quieter than the 110V 5CFM @ 90psi oil lubricated compressors I've been around).

The motor has a fair amount of axial play which is excersised due to the damaged/misbalanced pulley on the motor--I've got another pulley I'll try.

The pulley on the pump has no groove and is over an inch wide--I'm guessing it had a leather belt when this compressor was new.

With the tank pressurized I was able to blow another ice cream pail of junk out (slimey mixture of water and rust?).

I replaced the wiring from the pressure switch to the wall, but I need to get more in order to replace the wiring from the pressure switch to motor since I don't like the looks of it (I'm using 12 gauge stranded wire).

I bought some nice 3/8" Goodyear rubber air hoses at Mac's Hardware today.

I'm debating between Milton M-type air couplers and Milton V-type air couplers. I can buy the M-type locally, but I'll have to wait until the end of the month when I'm in a larger neighboring town which has a Northern Tool if I want the V-type. The V-type are a high flow version for HVLP spray guns (overkill right now, but I'm thinking ahead for when I can afford the air compressor I really want).

[msgross]

now time for some degreaser (might be too late!)

I also put a 20AMP 220v light switch on mine since it leaks air...

That goodyear hose is nice... I bought 100ft and a large reel of it at Harbor freight...

[ERASER5]

Speaking of draining water, I always recommend ditching the petcock valve and plumbing a ball valve out where it can be easily used. Easy to get to means you will use it more often. Plus the old petcock will not seal up if a some dregs get in the valve seat.

[72freak]

Old compressors are cool!!!! The tanks are the deadly part.....I believe the ones that are normally avoided in vintage tanks are seamed down the bottom.

[badpeanut]

Originally Posted by 72freak

Old compressors are cool!!!! The tanks are the deadly part.....I believe the ones that are normally avoided in vintage tanks are seamed down the bottom.

Is this due to corrosion in the seam?

Looking at the top picture there is a row of rivets at a seam up from the bottom a little ways.

[steppside69]

I was always told the reason for most tank failures was the lack of maint. to the tank (draining the water out of them). I worked in a local oil changing place while in high school and never seen anyone drain the water of change the oil in it, I was there for over a year!

[badpeanut]

I got the actual time required to fill a 60gallon tank on a 18.5cfm @ 90psi compressor today for 40psi, 90psi, and 120psi. It is roughly one-fourth the times I posted for this Green Behemoth, so I'm concluding this Green Behemoth does about 5cfm @ 90psi.

[Dan in Pasadena]

Nice old unit but your pictures have my OCD kicking in hard. I am dying to go at it with degreaser, putty knife and Scotch Brite pad. I bet it still looks good under all that!

['63GENIII]

Are those rivets I'm seeing running the length of the tank in the first pic?

[steppside69]

That's weird, welds on the end but rivits down the seam?
Posted via Mobile Device

[badpeanut]

I've got it partially cleaned (Simple Green works great). I'd like to change the oil but don't see a drain plug. Any ideas?

[steppside69]

Usually it is a pipe plug near the bottom, looks good cleaned up Eric

[Pop's C-10]

I love ole stuff like that