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2.5hp 40ltr unloader prob?

I have a 2.5 40L project air compressor and every now and then it just stops and hums and so i turn it off and when the unloader valve relessers i turn it on and it goes agin, why is it doing this? it also doesn't matter were the psi is at.

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Motor stalling during the fill cycle would indicate problems with the intank check valve, weak capacitor or low power to compressor. The unloader generally opens only when compressor reaches set pressure. Easy test. Unplug compressor with air in tank and remove the small airline at the checkvalve (brass valve in tank). Listen for air leak. Checkvalve is ok if no leak at brass valve. Test capacitor for 95% rated value. Replace as needed or test for low power. Good luck.

Posted on Aug 03, 2010


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