Air System Building too much Pressure

[Rawze]

(10-11-2021 )rtjohnson1982 Wrote:  Hey Rawze, I tried cleaning the air unloaded valve but didn’t help and I wanted to see if you could offer any advice on how to change the valve out? As in where it’s located, difficulty, etc. thank you sir!

I have never done it.. i replaced my air compressor and air dryer unit all at once, together when mine got to 800k miles to prevent such problems.

[snailexpress]

(10-11-2021 )rtjohnson1982 Wrote:  Hey Rawze, I tried cleaning the air unloaded valve but didn’t help and I wanted to see if you could offer any advice on how to change the valve out? As in where it’s located, difficulty, etc. thank you sir!

To change unloading valve compressor head have to be removed.
Did you try to disconnect compressor intake and exhaust from the air systen and spay WD40 into intake while engine is running to wash out soot deposits? Don't forget to put rug over exhaust to catch dirt.

[hhow55]

(09-09-2021 )rtjohnson1982 Wrote:  Hey Rawze, wanted also mention that it doesn’t start building excessive air pressure above 120psi until the knobs are pushed in. It will stay at around 120psi with the parking brake engaged.

Try adjusting the air governor, with the yellow brake button pushed in.

[Rawze]

(10-11-2021 )hhow55 Wrote:  

(09-09-2021 )rtjohnson1982 Wrote:  Hey Rawze, wanted also mention that it doesn’t start building excessive air pressure above 120psi until the knobs are pushed in. It will stay at around 120psi with the parking brake engaged.

Try adjusting the air governor, with the yellow brake button pushed in.

I a not a fan of that. If the governor is acting up past a simple cleaning, then its likely time to replace it out of safety concerns.