View Full Version : Craftsman Air Compressor Seized up

12-08-2012, 02:21 PM
I've got a Craftsman Air Compressor and I went to use it today and it wants to turn on, but doesn't (It sits there and hums). It is a small one, 4 gal, 1 HP. Anyway, where would I get parts to fix it and would it be worth fixing?

FWIW, it was made 10/2006 and I really haven't used it that much.

12-08-2012, 03:07 PM
I was going to say it hums because it doesn't know the words ... Are you sure it's seized up? Can you turn it by hand with the power off? If it turns and won't run it could be a starting capacitor. If it's seized it's most likely the piston; maybe you can dribble or spray a little penetrating oil in the cylinder. Key is a little, too much can hydrolock the unit if it does start.

12-08-2012, 05:53 PM
Is it oil lubricated or is it oiless. If it's either, chances are it was made by Campbell-Hausfeld and you can get parts from them. www.campbellhausfeld.com I believe.

If it's oil lubricated it has a sump that you put oil in. If its oiless, it has no sump and oiless compressors are all direct drive (no belt from the motor to the compressor).

Most oil lubricated compressors start rod knocking before they give out. There is really nothing to wear out except the rod bearings. The 'valves' that control air into the compressor to be compressed are nothing more than thin spring steel flappers that opn and close with the rise and fall of the piston(s). They carbon up and need cleaned eventualy. lI suspect like the other poster that you have a bad start capacitor as it 'hums'. Compressors experience fairly heavy start loads so compressor motors are all capacitor start or capacitor start and run.

A compressor has to be one of the most neglected power tools. Simple oil changes yearly and a yearly cleaning of the air filter and most compressors will compress air for an average persons lifetime.

Other than an oil chang and air filter cleaning, draining th condensate from the receiver is about all the maintenance ncessary. Forget to drain the tank and it rusts out eventually from the water (condensate) inside.

12-08-2012, 08:32 PM
i believe it is oiless but it was one of my first thoughts...contaminated/too low/or empty.

my first thought was actually how much care the tool was given? for the most part also things like to be used than left sitting. condensation can build up on the piston walls pretty easy depending oh what environment that its kept it. intake air filter are pretty poor as well and if it has been used in a harsh environment it will just suck the grit in.

probably not worth fixing but it depends on way too much stuff that nobody knows.

sears is where i go to get my craftsman parts. but someone has to figure out what the issue is to see if its worth fixing.

12-08-2012, 08:57 PM

99% of compressors lead an ugly, uncared for life and are still expected to work...everytime.:D

I've seen some ugly ones. Just looked at a 50 horse Sullair Rotary in a factory that went t i t s up. It's probably worth scrap value because if a rotary sits and the seals get hard, it don't compress well.

Besides, I don't need a 50 horse.

12-08-2012, 10:47 PM
Doesn't know the words....LMAO.

This is the closest, that I can find, to it. Mine is on wheels. It is a oil/lube type. The compressor and motor are a sealed unit...no belt. And it is a 110v model.

I left this out. When I first plugged it in it hummed, and on about the 3rd try It pumped like normal. It ran up to pressure and then kicked off. Since then, all it does is hum.

http://www.sears.com/shc/s/p_10153_12605_0 09164780...

12-08-2012, 11:48 PM
It's the start capacitor. Just be careful when you take the capacitor cover off. Most have dropping resistors, some don't. Grainger will have a replacement. Electrolytic capacitors can hurt you if you get your fingers across the terminals as in knock you on yiur butt.....

Change the oil and clean the filter...........

09-08-2017, 06:55 PM
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