Cool old compressor

[3literwithaheater]

My father in law is shutting down his shop. I found this compressor in the back room. He said it doesn't work. I'm thinking about putting a little work into it and reselling it. Opinions? How can I check the tank to know if its safe to use? What would it be worth in good running condition? I attached a picture. Not sure if I did it right. Appreciate any help

 

[The Cobbler]

old, looks to be well cared for , not all beat up, Speedaire. a proper test for the tank would be a hydrostatic test where it is pressurized with liquid to about 1.5 times it's working pressure ( i think)
did he drain it regularly ?
old compressor tanks are not something to be taken for granted or "trusted" for that matter. they can be very dangerous .

 

[Stillgottimefor1]

Yeah looks like a Speedair, as a general rule for me something that looks well maintained probably was so I would trust the tank. Those sell locally in good condition for around 150-200. I only buy them not working right and not as clean and pretty as that so I don’t know what it is worth. Often a screw comes out of a reed valve and lodges in a piston crown-no big deal. Parts are cheap and plentiful. If it didn’t run out of oil it should be easy to diagnose and repair. My 2c.


Sent from my iPhone using Garage Journal

 

[DD T/A]

I have a compressor that was made from an old WWII era LPG tank that shows some rust but not too horrible for it's age.
I spent a few months trying to figure out how to test it and came up with this:

Everyone says to hydro-statically test it and that it is no big deal. I called 15 places of which 6 or 7 were not in my city and state and they all acted like I was on a different planet when I asked them if they heard of "hydrostatic testing an air compressor tank". They would not discuss a price--not one of them.

Everyone says its "easy to do yourself"
Not one website has a clear How-to discussion or write up on exactly how to conduct it, or what they used; every post I read was: "Well when I did it I just put water in it and it's pretty obvious so I'm not going to explain anything else."
Or "I just took mine down to Fred's and they tested it for me for $5 no prob..."



.......hmmmm ya.....In other words I never got it done.


I have no clue who or where tests these things. And the best I could figure is someone said you could pressure it up with "an old grease gun". Nobody had any real specific instructions to help someone who has never done such a thing out. Just shade tree conversation at the most.

 

[larry4406]

I have a compressor that was made from an old WWII era LPG tank that shows some rust but not too horrible for it's age.
I spent a few months trying to figure out how to test it and came up with this:

Everyone says to hydro-statically test it and that it is no big deal. I called 15 places of which 6 or 7 were not in my city and state and they all acted like I was on a different planet when I asked them if they heard of "hydrostatic testing an air compressor tank". They would not discuss a price--not one of them.

Everyone says its "easy to do yourself"
Not one website has a clear How-to discussion or write up on exactly how to conduct it, or what they used; every post I read was: "Well when I did it I just put water in it and it's pretty obvious so I'm not going to explain anything else."
Or "I just took mine down to Fred's and they tested it for me for $5 no prob..."



.......hmmmm ya.....In other words I never got it done.


I have no clue who or where tests these things. And the best I could figure is someone said you could pressure it up with "an old grease gun". Nobody had any real specific instructions to help someone who has never done such a thing out. Just shade tree conversation at the most.

Our plumbers hydrotest water piping in all of our new homes. System is totally filled with water, then overpressure (air or hydrostatic water pump) is added to 120 psi pressure test. In the case of the tank, I would think you would close all ports except the upper most, fill tank completely with water, then attach a fitting and overpressure to 1.5x the tank pressure rating (assuming 1.5 is the multiplier).

 

[Lightning rod]

this is how its done using a pressure washer

 

[DD T/A]

Even though I'm not the subject, thank you very much for the information guys.

 

[3literwithaheater]

Thanks for the info. Speedair looks right. I got some more information. The issue with the compressor is that the unit wouldn't shut down once it came up to pressure. It would just run until the relief valve let off the pressure. .Ive got a boroscope on the way. Going to look inside the tank. If its not rusty inside my plan is to find the model number and order a new pressure switch. Ive watched a couple videos on maintenence. Should I change the intake air filter and the oil?
Thanks again

 

[larry_g]

Thanks for the info. Speedair looks right. I got some more information. The issue with the compressor is that the unit wouldn't shut down once it came up to pressure. It would just run until the relief valve let off the pressure. .Ive got a boroscope on the way. Going to look inside the tank. If its not rusty inside my plan is to find the model number and order a new pressure switch. Ive watched a couple videos on maintenence. Should I change the intake air filter and the oil?
Thanks again

You'll find that pressure switches are perty generic. You just need to know the operating range of the compressor, horsepower, and if the bleed off is in the switch or not.

lg
no neat sig line

 

[3literwithaheater]

Ok. Thanks.