My second air tank drops PSI very fast( 3-4 min) from 125 to 110 and then kinda hangs there until the compressor picks it back up. It never goes under 110psi. When I apply the brakes, the drop stops at 110 .
Sitting here now, engine off , both gauges are the same at 105# and it will drop overnight to 40-50 and zero in the couple of days.
I have no audible leaks and am heading towards the regulator on top of the tank , the brake pedal valve and maybe the relays.
Engine off, apply brakes and both needles move together with acceptable air loss.
Any help ?
Use a gallon garden pressure sprayer with a soap solution to spray bags, all devices and air lines. Any hardware store will have one for $10 or so. Air bubbles are much easier to see than a leak is to hear. A party bubble solution is the best if a store is in your area.
Pierce
It passes the bubble test.
Very little air loss after it is shut down and under 110#
One tank drops fast to 110
That tank has the regulator on it.
The check valves at the tanks leak. Foretravel stocks a bunch of them so they can be replaced. The guy that does the service work on motorcades says that is the first place he starts looking for leaks since they seem to always be bad.