# 1970 Kargard Air Compressor Unloader Not Working.



## AndrewT (Jul 14, 2020)

I have an older air Kargard compressor on our farm. The name tag it is a 1970 compressor. It seems to work fine but I’m not sure it is working to its fullest capacity. It pumped up to 100 pounds and shut off. I adjusted the spring and now it pumps to 130 and shuts off. It turns on at 110 pounds. It always has a 20 pound difference. Looking closely at the air tubes. One appears correct that it connects from the unloader housing on the pump to the air intake hose but the other one comes out of the pump but does not connect to anything. It seems like it should connect to the high pressure line as it is a made to fit tube. and ends near a capped t on the pressure line. The air compressor does work and has so for years. I removed the cap from the t and hooked up the tube. Once I turned on the pump, air came out of the bottom of the unloader housing straight below where the tube connects to the unloader. It look like an uncapped plug of sorts.. Because air was pouring out of the opening I unhooked the tube and recapped the t to go back to the original configuration. Also, I believe the unloader does not work as there is no air release sound once the compressor comes to full pressure and turns off. I did try to increase the tank pressure above 130 but the motor will not turn the compressor do to the air not being released over the pistons. Could the unloader be broken and the solution was to disconnect this tube and set the compressor to 100 pounds so the motor could handle the load?
This is on my father in laws farm that we inherited a few year ago and I am going through his stuff.
Please let me know if anyone has an idea on this compressor and if it's worth tearing into the unloader. Thank you


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## stevon (Mar 5, 2019)

Andrew,

That is the original centrifugal unloader tubing, It is supposed to stay open when compressor stops turning. If your pressure switch is piped into the check valve maybe you don't need the original and that's how they got around fixing this one if it's broken

Stephen


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## stevon (Mar 5, 2019)

Andrew,

Maybe the check valve was leaking and they heard air coming out of this valve which is normal. This was their attempt to fix the problem lol, but if the check valve is not working there will be a constant air noise until the tank is drained. The cheap solution is to buy a new pressure switch equipped with an unloader valve and pipe it into a new check valve with unloader port Killing two problems with one stone!

Stephen


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## AndrewT (Jul 14, 2020)

AndrewT said:


> I have an older air Kargard compressor on our farm. The name tag it is a 1970 compressor. It seems to work fine but I’m not sure it is working to its fullest capacity. It pumped up to 100 pounds and shut off. I adjusted the spring and now it pumps to 130 and shuts off. It turns on at 110 pounds. It always has a 20 pound difference. Looking closely at the air tubes. One appears correct that it connects from the unloader housing on the pump to the air intake hose but the other one comes out of the pump but does not connect to anything. It seems like it should connect to the high pressure line as it is a made to fit tube. and ends near a capped t on the pressure line. The air compressor does work and has so for years. I removed the cap from the t and hooked up the tube. Once I turned on the pump, air came out of the bottom of the unloader housing straight below where the tube connects to the unloader. It look like an uncapped plug of sorts.. Because air was pouring out of the opening I unhooked the tube and recapped the t to go back to the original configuration. Also, I believe the unloader does not work as there is no air release sound once the compressor comes to full pressure and turns off. I did try to increase the tank pressure above 130 but the motor will not turn the compressor do to the air not being released over the pistons. Could the unloader be broken and the solution was to disconnect this tube and set the compressor to 100 pounds so the motor could handle the load?
> This is on my father in laws farm that we inherited a few year ago and I am going through his stuff.
> Please let me know if anyone has an idea on this compressor and if it's worth tearing into the unloader. Thank you
> 
> ...


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