Another thing that would be an easy check, some compressors have a speed sensor on the rear of them, this is to ensure that there is no drive loss due to clutch or belt slippage, if that speed sensor is malfunctioning or not connected properly it will let the compressor run a bit and when it senses the engine speed is not consistent with the compressor speed it will shut it down. Just another item to check, if it is a Nippo compressor it likely has one.
Brian

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Brian W. Heitman

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