# Compressor not fully pressurize



## MightyMo (Jun 23, 2019)

Hello everyone. I was given a little 8 gallon, 2HP Central Pneumatic compressor (model 40400) from my neighbor that said it wouldnt pressurize and didnt want it anymore. I plugged it in and it started to pressurize but only got to 55 or 60psi and stopped filling up but kept running. Its suppose to go to 115psi and the valve is wide o I let it continue to run for about 15 mins but never got any higher. I shut it off thinking it might have a leake somewhere but no leake and there was no hose connected to it so I'm stumped on this on. What do ya'll think?


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## stevon (Mar 5, 2019)

MightyMo, 

First thing to check is the oil level. 
The pump head theoretically "ejects air" at 150 psi into the check valve to overcome pressure in the tank. even with no check valve the pressure should at least come to 100lbs PSI. If it doesn't the cylinder head gasket, damaged piston, broken piston rings, scored cylinder walls or other bore issues, damaged valves in the head would cause the issue.
Sounds like a pump rebuild or replacement is in order

Stephen



MightyMo said:


> Hello everyone. I was given a little 8 gallon, 2HP Central Pneumatic compressor (model 40400) from my neighbor that said it wouldnt pressurize and didnt want it anymore. I plugged it in and it started to pressurize but only got to 55 or 60psi and stopped filling up but kept running. Its suppose to go to 115psi and the valve is wide o I let it continue to run for about 15 mins but never got any higher. I shut it off thinking it might have a leake somewhere but no leake and there was no hose connected to it so I'm stumped on this on. What do ya'll think?


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## stevon (Mar 5, 2019)

MightyMo

Some replacement options:

PMP11MK246FC 
https://mastertoolrepair.com/hp-high-speed-pumpmotor-assy-air-filter-pmp11mk246fc-p-8227.html 

https://www.aircompressorpumps.com/pump/pmp11mk246fc/434 $199

https://picclick.com/Air-Compressor-Pump-and-Motor-Replacement-…2-hp-311906195234.html

https://www.alibaba.com/product-det...spm=a2700.details.maylikeexp.3.42b8201eNT0JsA

Stephen



MightyMo said:


> Hello everyone. I was given a little 8 gallon, 2HP Central Pneumatic compressor (model 40400) from my neighbor that said it wouldnt pressurize and didnt want it anymore. I plugged it in and it started to pressurize but only got to 55 or 60psi and stopped filling up but kept running. Its suppose to go to 115psi and the valve is wide o I let it continue to run for about 15 mins but never got any higher. I shut it off thinking it might have a leake somewhere but no leake and there was no hose connected to it so I'm stumped on this on. What do ya'll think?


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