Question about Porter Cable Cable 4.5 Gallons 150PSI Job Boss Oil - Free Mobile Air Compressor - C3151

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Cut off switch problem

The compressor will build pressure but the cut off switch wont engage and cut it off. is there any adjustment or something i can clean to make it work right, or do i need to buy a new switch?

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The pressure switch will trip off when the compressor reaches the rated setting (usually 120 ~150psi). If the compressor keeps running untill the safety pops releasing air (usually about 160psi) then the switch is most likely problem. I use SquareD switch from WWW.Grainger.com. However if the compressor keeps running but never pops the safety and only reaching around 90 to 100psi, then you could have several other issues including: leaking fittings (check with soapy water), worn cylinder and piston (on oilfree compressor examine cylinder from below and look for scratches), leaking valves on oil type compressor. Please email with your finding and any questions Good Luck

Posted on Jan 28, 2009

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