compressor problem

[83mulligan]

have an old craftsman 12 gallon, 2 hp compressor. It only builds pressure to 80 psi on the tank guage then it shuts itself off. Outlet guage is stuck at 85 (no adjustment when knob is turned). Any advice???

 

[Moody Blue]

Re: compressor problem

Is this a new compressor to you?

Probably a defective pressure switch OR the switch is adjusted to cut out at 80PSI.

As for the output gauge, I would guess that the gauge is defective. To verify, bleed the tank pressure and watch the gauge. If it doesn't move then the gauge is toast.

 

[Splat]

Re: compressor problem

have an old craftsman 12 gallon, 2 hp compressor. It only builds pressure to 80 psi on the tank guage then it shuts itself off. Outlet guage is stuck at 85 (no adjustment when knob is turned). Any advice???

Try turning the knob while using air. All of my regulators are more acurate while air is being bled through them. Also the regulator pressure may be set higher than the pressure the tank is currently creating. Have you tried turning the regulator knob all the way to the extremes?

Bill

 

[83mulligan]

Re: compressor problem

Is this a new compressor to you?

Probably a defective pressure switch OR the switch is adjusted to cut out at 80PSI.

As for the output gauge, I would guess that the gauge is defective. To verify, bleed the tank pressure and watch the gauge. If it doesn't move then the gauge is toast.

I borrowed it from my dad, who took my pancake compressor. I needed some higher cfm for a couple air tools. Is the pressure switch easily adjusted?

 

[83mulligan]

Re: compressor problem

Try turning the knob while using air. All of my regulators are more acurate while air is being bled through them. Also the regulator pressure may be set higher than the pressure the tank is currently creating. Have you tried turning the regulator knob all the way to the extremes?

Bill

thanks bill, i'll give those things a shot.

 

[rwise]

Re: compressor problem

Should not be hard to adjust it for higher pressure, if you turn it to high it will pop the pop off valve (over pressure relief) if this happens it will reset when the pressure drops low enuf. You could also remove the regulator and pull full tank pressure (if your tool/s can handle it), but I would start with the gauge, if it does not work correctly, replace it.

 

[83mulligan]

Re: compressor problem

The regulator guage drops when I pull the air pressure relief. They both do. The compressor shuts off at about 85 psi though. Is there an adjustment for this? Shouldn't it build to 140 and shut off then kick back on around 120?

 

[v1_0]

Re: compressor problem

Maybe you could find the owners manual, either online or from your dad. It might tell you how to troubleshoot the pressure, or even how to adjust it.

-V

 

[sportsmanphil]

Re: compressor problem

Most compressors with a built in pressure regulator, the knob has to be pulled outward or pushed inward when turned, kinda like a child proof medicine bottle. And to see where its new setting is at, you must release air.

However that should not cause the pump to shut off early. Whats the max PSI the compressor is rated for? Excessive moisture can enter the pressure valves, more easier in smaller tanks, and cause them to malfunction. Drain the condensation often, more often the smaller the tank is.

 

[Moody Blue]

Re: compressor problem

Most compressors have adjustable pressure switches. There is a cut out (high pressure setting) and a cut in (low pressure setting). They are typically a square box about 3" x 3" x 3" and sometimes the power switch is incorporated in the same housing. Take a look to see how the cover comes off.

Must take extra caution when fooling with these. Setting the pressure too high could exceed the pressure rating of the tank and result in a potential explosion. The relief valve is SUPPOSED to prevent that but do not rely on them.
There is also line voltage (110vac) present in there so be careful.

Inside this box should be two spring loaded screws. One for cut in pressure and one for cut out pressure. Often there is a diagram INSIDE the cover identifying what is what. Turning the screws tighter will increase the pressure and loosening the screw will decrease the pressure.

Take a look around and see what you can find. Safety first. Adjust in small increments then check the results.