DIYbanter - View Single Post - Any tips for finding air compressor leak?

wrote:

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I would consider putting a valve at the tank inlet and see how fast it
leaks down with the valve closed and preventing air from getting to the
compressor.

The problem with that is there is a "Christmas tree" screwed to the
tank. Off of it is: the pump output, the unloader, the pressure guage,
the pressure switch, the pressure relief, and the outlet port. So there
is no isolating the tank, easily. Bob