Compressor won't start up ...Ideas?

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gdizzle

gdizzle

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Hey guys, I have this old HarborFreight pancake 2hp compressor I bought 15 years ago. It gets minimal use, nails, pumping tires. once a month, max. Anyhow lately it won't start, it tries for a few seconds then it stalls and will blow the breaker. If I shut it down before the breaker blows, I can turn on/off 10 times in a row and finally it will continue to run and have no problems...until a few weeks later when I try to start it again.
It has oil, though it has to be years old. It is either going in the trash, or can I try anything to try to fix it?
 
Gonna take a wild guess.............the capacitor is shot on your motor; it, the capacitor gives a little extra "kick" to start the motor turning, with out it the motor goes "locked rotor" . Might be able to get a replacement, it is located under the "bump" on the side of the motor, they are rated/sized in "micro Farads" (uF ) , with compressor unplugged, short across the terminals with a screw driver to ensure it is unloaded before unhooking it, you could get zapped if you don't..............OR, the brushes in the motor are worn out, might be able to get replacements........................ OR, junk it and buy a new compressor, it doesn't owe you a thing after 15 years
 
I had one that needed the commutator and brushes cleaned, you can try that. once they get gummed up they loose a lot of energy.

Of course the one I had had a DC motor with brushes.
 
Most of those pancake or small compressors burn up because they take them out in the driveway and try to run them on a long extension cord that is to small to carry the current.
 
Unfortunately this can be a number of problems.........start cap, start switch (centrifugal), start relay if used (works on current and or voltage to delay start cap) start winding damaged/ burned / partly shorted.

"What I'd do" likely. If you can't test the start cap, and that can be difficult, just replace it. Take the thing apart and examine the mechanics of the start switch........is the spring operated collar on the shaft OK and free? Not sticking? Is the switch in good shape, the contacts OK? How about SMELL? Does the motor smell like or the windings LOOK like they are burned?

And as others have said, make SURE you have an outlet/ extension with enough capacity (ampacity). The problem EG with long cords is that they drop the voltage down, and don't "give" enough to start the thing.
 
67Dart273 said:
Unfortunately this can be a number of problems.........start cap, start switch (centrifugal), start relay if used (works on current and or voltage to delay start cap) start winding damaged/ burned / partly shorted.

"What I'd do" likely. If you can't test the start cap, and that can be difficult, just replace it. Take the thing apart and examine the mechanics of the start switch........is the spring operated collar on the shaft OK and free? Not sticking? Is the switch in good shape, the contacts OK? How about SMELL? Does the motor smell like or the windings LOOK like they are burned?

And as others have said, make SURE you have an outlet/ extension with enough capacity (ampacity). The problem EG with long cords is that they drop the voltage down, and don't "give" enough to start the thing.
Click to expand...

ALSO MAKE SURE THE UNLOADER is operating, if it has a tank and pressure valve. The unloader removes pressure from the cylinder head so the thing will start. Sometimes these are an "automatic" deal built into the tank check valve, and sometimes there's a separate tube to the pressure switch which operates the unloader.
 
most towns have recycling areas to drop things like that off. If no town recycler take it to a metal recycler and maybe get a little money for it. I took an old refrigerator and got $15.00 at metal recycle place.
 
Thanks everyone. I ended up just buying a new Craftsman Hotdog compressor. Sounded like the time spent trying to fix my old one was hardly worth it. I still can't believe I got 15 years out of it. thanks everyone.
 
grab the tank for a "can of air" when you need one out in the front yard for a tire or something.
 
^^But be careful with old tanks and consider a home brew pressure test (water). Friend JUST gave me an old compressor......pump still runs but tank has a rusted hole. They were recalled, he said

air compressor explosion - Google Search:

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67Dart273 said:
ALSO MAKE SURE THE UNLOADER is operating, if it has a tank and pressure valve. The unloader removes pressure from the cylinder head so the thing will start. Sometimes these are an "automatic" deal built into the tank check valve, and sometimes there's a separate tube to the pressure switch which operates the unloader.
Click to expand...
This. Very common.
Had one that uses a bleed off valve in the tank fitting.
Just needs to come out and be cleaned.
 
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