Air compressor pressure not regulating

Usually you cannot adjust the cut out pressure of the tank/motor itself, this is why they have regulators, which regulates the pressure flowing down the air lines (regulators like these dont regulate actual tank pressure cutout). To regulate air flow using the regulator knob, you actually have to have air flowing through the hose while you make the regulator/pressure adjustments as regulators regulate pressure DOWNSTREAM from the actual regulator itself.. so air flowing through is a must. Attach an air blower or something similar and let air start flowing through the hose. Now turn your regulator knob in the "-" direction to decrease regulated pressure. It is best to bring pressure all the way down to "0" first, then open the regulator up (by turning to the "+" side) and pressure will rise until you get to the desired pressure needed for the air tool in use. The tank pressure will still be between 80-125 PSI as the motor regulates and keeps the pressure in the tank between these values automatically, but your line/hose air flow pressure will remain at the regulated pressure (say 40 PSI or whatever you set using the regulator knob).

Hope that helps and makes sense.

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