Sears Craftsman 3-Gallon, 1.5 HP Air Compressor Hums

This compressor has a 33 gallon tank and a 3 to 5 hp (rated)motor. Sears , however, rates their motor power rather differently. I would guess that the actual hp is more like one to one and a half horsepower, going by the amp draw. Usually, a 3 to 5 hp range compressor will only run on 220v and this unit is 110v.

What sound? A click?

Worn out piston ring How can this be oil less compressor motor

When mine hums and trips, it is one of two things, Not warm enough, only does this when it is cold out, and 2 would be not enough juice, I have to have a 20 amp breaker or it doesn't run. And if I use a cord, it has to big. The slightest drop in amperage and it will not run, yours might have the same problem, mine is only 1 1/2 HP. It draws some 16 amps at start up and then idles down to 13 to run. A 15 amp breaker, forget it. Cold out, forget it. It wasn't just mine though, we did a house last winter and made one bathroom heated with a gas heater with 3 compressors in there just to keep them warm, there was no room for us. Hope this helps.

sears craftsman air compressor motor hums. replaced start capacitor still hums

Is your air pressure regulator set very low? Try adjusting it to a higher pressure

my ace air compressor which is 26 gallon 5 hp will not get over 60psi what is wrong with it please?

if they are oilless compressors then the rings are worn

check your popoff valve first. it is the valve with the ring hanging on it. You will hear the air rushing.

If you don't hear any air rushing, you may have fried the piston rings or broke/chipped the piston(not your fault)..especially with oiless compressors