United States Air Compressor Co. 1947

by Justin Bond
(Fayette, Utah)

United States Air Compressor Co. 1947

United States Air Compressor Co. 1947

United States Air Compressor Co. 1947
United States Air Compressor Co. information plate
United States Air Compressor Co. pump
United States Air Compressor Co. information plate

This air compressor sat on the side of a small store in Fayette, Utah. The store was purchased by the last owner in 1947, just after he got out of the war in the South Pacific. So he would have bought the compressor new when he bought the store. The store was closed in 1986. The family that owned the store was cleaning up their yard and told me I could have it if I hauled it off.


I put a new motor, a new pressure switch and a new gauge. and it fires up and runs fine.

However, there are times when it is sluggish and runs slow and then trips either the motor breaker or the panel box breaker. If you can tell from the picture, I have the unloader taken off to see if that might be an issue.

It is a 220 5hp Century electric motor. 3450 rpms. It has a 6 inch pulley on the motor side.

Also, from the pictures you can see there are slots for two belts on the compressor. I was wondering if it needs two belts to run properly or what the purpose of that is.

If anyone is familiar with this unit, I would appreciate any help in figuring out why it runs sluggish at times. At other times it starts up and runs perfect to 120 psi when it shuts off.

Thanks

Justin

Comments for United States Air Compressor Co. 1947

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Apr 11, 2016
USACC
by: Doug in s.d.ca

Good about the drive pulley.

I'm thing the filter is on a threaded pipe fitting, so maybe a lawnmower shop would have something that would fit.

Good luck.

Apr 11, 2016
Smaller made the difference
by: Justin Bond

I did put a three inch pulley on the motor. That changed everything. It does not trip the breaker anymore. It pumps up nicely to 110 psi, (although slowly) trips the pressure switch and blows out the unloader.

I agree I do need to fashion an intake filter. If you can see from the picture the old intake filter has rusted off. I wonder if I can find something to retro fit it.

Thanks

Apr 10, 2016
pump
by: Doug in s.d.ca

I dunno whether running it that fast is causing the binding, but I think you should definitely get the smaller pulley to lower it to the spec'd range. It may be overheating due to the high speed...unless you have a spec for it to run.

Also, you should add an intake filter ASAP. It doesn't need to be anything special, but should be large so as not to restrict air flow too much.

Apr 10, 2016
Compressor air lines clean - thanks!
by: Anonymous

I did take several of the air lines off and they are all clean. I did change the oil and drained all the water out. The tank was about half full of water. Every else else on the unit looks really clean.

I did find some specs on the compressor from someone who has the same unit on this site. The post said: should be 1 to 3
h.p. motor depending on motor pulley size, 1 hp at 280 rpm and 3 h.p. at 684 rpm at 12.3 cfm.

I think my motor and pulley set up are running the pump too fast. My compressor pump is running at 1293 rpms. I can slow it down to 646 by putting a 3" pulley on the motor. I wonder if that will help.

Apr 09, 2016
Thanks for the replies
by: Anonymous

Hi, there was no motor on it but I did find some info for the compressor. 1 to 3 h.p. motor depending on motor pulley size, 1 hp at 280 rpm and 3 h.p. at 684 rpm at 12.3 cfm. If I want this compressor to run at 684 rpm I need to put a 3 inch pulley on the motor. I think the pulley I have is too big and runs the compressor too fast.

I did change the oil. I could not find any filters for the intake. And I have not taken any of lines off to check for dirt. I need to do that.

Apr 08, 2016
USACC
by: Doug in s.d.ca

Might be underpowered, and yeas, generally if there are two grooves, you need two belts for them to last.

Was there a motor on it? Please give the specs if so.

Apr 08, 2016
US Air compressor
by: Jim O

Justin,
Have you taken any of the air lines off to see if they are plugged with dirt of corrosion, maybe a kink in a line. Have you changed the filters, changed the oil? Checked amp draw on the motor?

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