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I have a Hitachi EC12 compressor. At 120 psi, the

I have a Hitachi EC12 compressor. At 120 psi, the motor shuts off, but it relieves pressure until the motor starts again. This short cycling causes the motor overload to trip after about 15 minutes. The pressure relief valve is not bleeding the system down.

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  • terijan Feb 07, 2010

    It makes sense to me. I will check it out tomorrow.
    Thank you.



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There is a relief that allows the pressure to come off of the cylinder head to enable easier starting when it restarts. Sounds like that relief is doing what it should but the check valve between the compressor and tank is bad.
Somewhere in the line from the compressor to the tank there is a check valve and that is no holding. Probably has dirt under the seat.


Posted on Feb 06, 2010


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