Air bleeds from compressor after charging.
How do you know if it is the check valve?
How do you clean check valve?
Checked all lines in and out of tank and compressor.
Unloader valve discharges a lot of air while compressor operating. Compressor is a Coleman.
Where the air bleeds from is important.
The first step is to have a look at the the sitemap for the pages on this site that explain the operation of the UNLOADER VALVE and also the operation of the CHECK VALVE.
“How do you know if it is the check valve?” The answer to that is described on the pages.
Also noted is the typical location of the check valve where the line from the top of the compressor pump enters the tank. Often, there is a tee off of an air line over to the pressure switch, and this is the line that goes, again normally, to your unloader valve.
It sure sounds like your check valve is leaking. Dump all the air from the compressors and unplug it before you start disassembling the line into the tank to pull the check valve, inspect it, make sure it closes, and reassemble.
Would you please provide the Coleman compressor model number and upload a photo or two of it too so we can all see what the model looks like?
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