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Air Compressor Help

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sammy004

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Hi guys I have a air compressor and at the motor it sparks like crazy and just dies so in order to get it going back again I have to take a long screwdriver and spin the fan a bit and it starts back up but sometime that doesn't even work. I have added pictures to explain my problem a little better and I'm not registered on any engine forums so I thought I try it here to see if anyone can help me out.


On this pictures you can see it sparking quite a bit.
**broken link removed**
**broken link removed**

Here is whats going on the cirled in red causes that sparks, what can I do to it to fix it? as you can see it is burn up pretty good.
**broken link removed**
**broken link removed**
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If anyone can tell me what to do it will be greatly appreciated.
Thank You
 
The short black blocks that slide in the brass square tube are called brushes and yours are worn out and need replacing. However, sparking like that is normally a sign that one of the armature windings may have gone open circuit. The way to test the armature is to remove the (very worn) brushes and to measure the resistance between opposite commutator pads (the rectangular copper blocks that the brushes rub on). So pick two pads that are opposite each other and measure, then move to the next two until you have done them all. The readings should all be close to each other. If they vary much then you have a winding that is open circuit.

Mike.
 
It's a universal motor.

It looks like it's series wound so don't operate it without a load whatever you do.

Some sparking is normal but that looks excessive.

Does it spark just as much on both sides?

Are both brushes just as badly worn?

The sparking could also be a symptom of a badly worn down brush and might go away when it's replaced.

By the way, replace both of the brushes, even if only one is warn down to the end.
 
It looks like the contact rods in the brush are through to the other side. You can see small grooves in the commutator where they are digging into it. That's what is most likely causing the massive sparkage.

As was already mentioned, replace both brushes.
 
I had sparking that bad when my brush housing was damaged. My point is, the brush and commutator is most suspect. If you replace the brushes and still have problems, look into having the commutator reconditioned.
 
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The brushes are gone as was covered. However, the comutator looks less than good also. If that com is as bad as it looks it will eat new brushes. I would pull the com and take it to a motor place where they can turn it. If you have a good lathe or friend with a lathe you can do it yourself.

Based on the images I would replace the brushes and turn the com.

<EDIT> Wouldn't hurt to clean up the brush housings and true up their bottoms too. </EDIT>

Just My Take
Ron
 
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Coo. Reduction on arcing is always tricky. I built motors, the sparks seem to reduce based on the coverage of the brushes on the contacts.
**broken link removed**
 
So are these the brushes circled in yellow..... the little blackish block that slides in?
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So if I replace them it will not spark anymore? The sparking is only on one side and where can I buy those brushes from?

I can get more pictures for you guys if it'll make it easier for you guys to help me I can probably get a small video as well. I really appreciate your guys help thank you so much.
 
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Yes, those are the brushes and the com (commutator) is what they ride on. The com should be smooth bright copper especially smooth. Thus I suggested earlier "turning the com".

Since you are in Canada I really don't know where to suggest for buying brushes unless you can locate the motor manufacturer? I use suppliers like McMaster Carr Supply down here in the US. Measure the brushes (guess at the original length) and any good motor parts supplier should be able to help.

Best I can come up with...
Ron
 
Thats the first one of those air compressors I have ever seen make it through a entire set of brushes! They usually burn out the motor long before the brushes go.

I have worked on at least a dozen or so that are built with the exact same motor and oilless compressor.
Craftsman, Camble Housefield, Black and Decker, Dewalt, Ingersoll Rand, plus the harbor freight cheapos, and likely a few others all used that base compressor and motor system at one time. They always fry the motor at some point just after the warranty is up.
So congratulations! You beat the odds! Unless of course it has a partially shorted winding that caused it to burn up the brushes. If it has low running hours on it since you bought it that would be why the brushes are burned down to nothing.

Still I would recommend tossing it and buying a real air compressor. Those high speed oilless compressors like yours are just not worth rebuilding.
 
Thats the first one of those air compressors I have ever seen make it through a entire set of brushes! They usually burn out the motor long before the brushes go.

I have worked on at least a dozen or so that are built with the exact same motor and oilless compressor.
Craftsman, Camble Housefield, Black and Decker, Dewalt, Ingersoll Rand, plus the harbor freight cheapos, and likely a few others all used that base compressor and motor system at one time. They always fry the motor at some point just after the warranty is up.
So congratulations! You beat the odds! Unless of course it has a partially shorted winding that caused it to burn up the brushes. If it has low running hours on it since you bought it that would be why the brushes are burned down to nothing.

Still I would recommend tossing it and buying a real air compressor. Those high speed oilless compressors like yours are just not worth rebuilding.

For something I got for free I think this is a learning experience thanks to some of the guys here that are actually helping instead of discouraging one. Thank you very much!!!
 
For something I got for free I think this is a learning experience thanks to some of the guys here that are actually helping instead of discouraging one. Thank you very much!!!

Are you intending to repair or bin it?
 
Are you intending to repair or bin it?

Well Obviously repair it if I can. Just in-case something like this happens in the future with something other then my air compressor I will know what to do. If i wanted to bin it I would of just bined it and not come here Right?
 
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