Hi everyone,
My current neighbor at MOT just went to dump and his brakes would not release although he has 125 PSI.
He had some work done on his step a couple days ago where they increased the pressure
99 U320
All of them? That's interesting. It's not seeing the pressure I would think.
Well I don't have a solution I would be wondering what the cause is? At least he's in the right place to get it fixed.
Yes he is
There is a relay valve that the treadle valve activates that controls both rear maxi releases. If he can find it try tapping it.
Could be a problem with the PP-1 valve. That's the one connected to the push-pull knob on the dash. They make repair kits:
Bendix PP-1 Repair Kit (https://www.foreforums.com/index.php?topic=27892)
I'll let him know.
Thanks
My suspicious mind gets triggered when a new problem creeps up after "servicing." In this case a system pressure increase that ordinarily shouldn't have been a problem, has now caused a valve failure in a life-critical system. I'd start a new ticket and have, at least, the air portion of the braking system thoroughly inspected and parts replaced as necessary.
Most people see an air pressure gauge, a red light and an annoying buzzer. I see a pneumatic logic system designed to provide controlled application, rapid release, dual braking circuits, air pressure preservation in case of a broken air line and fail-safe brake application. If you don't do a DOT air brake test every morning, well, best you go first. I'll watch the show from the back.
I had that happen in Rocky Mountain NP in my Buffalo Bus. I set and released the brakes at least 20 times until it finally let go. Took a while as I had to build pressure quite a few times. This was a DD-3 can but could happen to ours U300 also.
Pierce
Good morning everyone,
My neighbor started his coach this morning and cycle a parking brake on and off a couple of times and they released.
Thanks again for all the input