Compressor / Slow air build up at first start

Could it be your compressor is getting wore out? I had a similar issue with mine and that seemed to be the problem. The only way it would build air was if I had the motor at high idle. I replaced the compressor and problem solved.

You could start be replacing your governor, its the cheapest.

 

Going to depend on what type of air dryer you have.. the Bendix ad-is dryer will fill the primary till 90 psi first then the secondary.there may be pressure protection valve sticking in this dryer meaning replacement of the whole dryer.

Otherwise if you are running an older dryer there may be 1 way check valve sticking on the secondary tank from your wet tank.

have you verified the tank pressure to rule out a guage issue.

 

My guess would be to change the unloader on the top of compressor. it costs approx $12.00 for the kit. it can cause the problem your having & less money to try than a lot of the process of elimination tactics, that I know SOOO well.

 

Air governor. Same bs with my truck couple of weeks back.

 

the last time we got the same issue with '96 Volvo FH 12, governor line was cloged with old oil deposits and air drier supply line (aluminium) got so much oil deposits inside, that could not be pumped well and was very hot

we changed Governor and air lines, truck keeps running

 

Were you able to get this fixed? My C12 is doing something similar, was just thinking it was getting worn out. Going to try Heavy Haulerss idea first. Sounds cheaper than $375 +/- for a Bendix compressor.