Truck Air Dryer Not Purging

Check to make sure air flows through purge control line when compressor is unloaded.

Truck air dryer not purging. Oil entrained in purge air from a vehicle air dryer is directed through a purge air cleaner to remove the oil before discharge of the purge air to the environment. 5) air dryer does not purge or exhaust air. If it builds air with the governor removed, verify that the air dryer is not sending a signal to the governor to unload the compressor.

Even though pressure shows full in wet and dry tanks: Replace with conect voltage air dryer. Cat 3406e doesnt stop building air pressure and the air dryer wont purge.

We replaced the air dryer and the regulator on the air compressor. The problem occurs when the air dryer keeps purging way too frequently. I also tried plugging the little air vent line where the thing keeps purging the air out of for a sec and water started draining out the bottom of the air dryer, so i quickly unplugged the line before i fucked it up.

If no air is coming from the air dryer signal line, change the governor. So older air brake systems are going to have a wet tank. The air dryer is going to be between the compressor and the wet tank.

We figured that the air pressure was dropping so quickly because after every purge, the air dryer valve wouldn't close completely, and continued releasing air. It would release air every 40 seconds every time air pressure gauge needle reached 125 psi. For some time the truck was spitting at 120.

Every time compressor cuts out at full pressure governor sends air to dryer purge valve. I know i do not have any air leaks as i only lose about 5 psi over 24 hours. Possible likely causes is a bad purge valve or a pin hole in the sense line to the governor.