Thank you for your question.
I am sorry you are having a problem with the air compressor. On most capacitors, it does not matter which wire goes on which terminal. To be sure, look at the old capacitor. If it has a plus and negative marked on the capacitor it will make a difference. Just reverse the wires and see if runs differently. If you have a meter that will check capacitors, I recommend checking both capacitors. If both of the capacitors are fine, the problem is likely a failed motor. If it had over heated when the start capacitor was bad it could have damaged the motor windings.
I also recommend plugging the compressor into a different outlet, to be sure the outlet is not causing the problem.
Please reply below with more details if you need further assistance.
Here is a link to order any parts you need.
Sears Parts Direct
If you do not feel confident repairing this problem yourself, then you can have it repaired by a Sears technician. Here is a link that will provide the nearest drop-off locations:
Sears Home Services
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