Air Compressor leak-down

[FD611V]

My 1993 Sears 4 Hp 25 gal. Air Compressor has always had the leak-down. By that I mean, when I used the compressor and leave it with 120 lbs. of air the compressor goes back to "zero" lbs. within 10 hours or so.

Does most air compressors have a natural leak-down to them?

I'm not really overly concerned here, as I generally restart the compressor when I'm needing to use it.

 

[Charles (in GA)]

No, thats not normal. does the compressor have a ball valve to shut off the tank, or does the tank feed a built in regulator directly?

Both of my compressors have three openings into the tank, the inlet check valve from the compressor, the outlet ball valve and the tank drain. They both hold pressure for days, weeks and months at a time, if the ball valve is closed.

Charles

 

[Lightfoot]

take the tank check valve out and clean it. that would be where i would start, and it won't cost you anything, unless you have to replace it. Also the fitting at the hose (either end) could be leaking. some soapy water will tell the tale. It could also be the drain shutoff leaking a bit. Lots of things it could be and it may be more than one.