615C Not build air past 60 PSI

[Nige]

KS is that schematic from a 615?

It's correct for the Serial Number according to SIS. Fits everything up to 9XG1824. The machine itself dates from 1997.
Actually the Air Dryer Gp is listed as an Attachment (option) so it might be that this particular machine doesn't even have one. The system isn't exactly specific regarding whether it does or not.

And if it does have a dryer, I seriously doubt it's ever been serviced.

That may have something to do with the problem. Who knows.?

 

[Truck Shop]

The system isn't exactly specific regarding whether it does or not.

Well if it does its easy enough to bypass

 

[kshansen]

KS is that schematic from a 615? because if it is-that is one really outdated air dryer.
A real early version of a Wabco 1800 style. Those were problematic at best.
And if it does have a dryer, I seriously doubt it's ever been serviced.

What you mean you have to service them? The few I worked with sure had some nasty stuff inside when I opened them up!

 

[Truck Shop]

What you mean you have to service them?

Once a year.

 

[precision dirt]

Don’t know if this was ever fixed but I had same problem on my 615. Turned out the air hoses that are ran through the wall of scraper bowl to the rear had blown. It’s encased and you don’t hear anything.