why air coming from our compressor has bad smell same as burned oil

by eddie bantog
(epza rosario cavite philippines)

last time our copressor motor was burned (50hp) it takes a long time to change it almost 2 months,when we install the new motor,the air coming from compressor was very bad smell like burn oil

please help me...
Not knowing anything about the circumstances of the original motor failure or the make or model of your air compressor makes it difficult to try and help you figure out the problem.

The air coming out of the compressor has gone, I expect, into an air tank or other reservoirs in your compressed air system.

If those air reservoirs have not been emptied of water regularly, and if they have now sat for two months with no air moving through them, I would suspect you have a pretty good case of mold or bacteria growing in the tanks that is now being expelled downstream as you now start using the air.

Short term...? Install a line to the outside of the plant and run the compressor long enough to void all the tanks and lines of old air and try and blow out the contaminants.

Long term...? Depends on whether aggressively blowing out the air system works.


Comments for why air coming from our compressor has bad smell same as burned oil

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Aug 15, 2014
Piston seals
by: Bill

If you use your browser with this search string "compressor piston kit" you will find lots of images of piston seals.

No, rotary screw air compressors do not have piston seals as they do not have pistons. The rotary screw compressor compresses air in a chamber with two screws, bathed in oil. Then, the air stream passes through an oil separator before getting to the air mains. If the oil separator is not working properly, oil will be getting into the air.

Aug 15, 2014
piston seal
by: Anonymous

Hi Bill please give me a sample image of piston seal..did screw type compressor have piston seal also??TY

Nov 14, 2013
already done
by: eddie

we think of it before...we disconnect compressor pipe from the tank,put new oil,cleaning oil separator,and running for almost an hour,but still the same...bad smell (burn oil)coming from the compressor...thanks for your reply...
Well then, I expect that you've got some piston seal issues, with oil wicking past the seals into the air flowing into the tank.

That's the only way I can see that oil (and oil smell) can be getting into the air stream from the compressor to your air tools or equipment.


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