# Old Sears craftsman compressor bogs down shuts off



## Devaer28 (Nov 22, 2020)

I have a Sears craftsman 4ph 20 gallon air compressor that builds wire to about 35-40 pi’s then bogs down and eventually popping the reset on the motor. I have put a new pressed switch with no luck. Any suggestions?


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## iowagold (Jan 22, 2020)

change out the oil first and look for trash in the old oil..
from there
tear down..
check the valves in the head and the inline check valve.
i assume you are 4 horse power and not 4 phase.


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## stevon (Mar 5, 2019)

Devaer28

Sounds like your run capacitor has gone bad or that your start capacitor switch is stuck "on"

Stephen



Devaer28 said:


> I have a Sears craftsman 4ph 20 gallon air compressor that builds wire to about 35-40 pi’s then bogs down and eventually popping the reset on the motor. I have put a new pressed switch with no luck. Any suggestions?


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## iowagold (Jan 22, 2020)

if you have a clamp current meter check the current draw.
click here for the test equipment page if you need a clamp meter
that will tell you if the start switch is sticking..
if you are real good with electrical you can tear down the motor.

snap a few pix of the motor tag for us.


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