MCI MC-12 overpressure and no park brake release

[robertglines1]

what are your working conditions---concrete?gravel?dirt?

[vintoolong]

well packed gravel.

[buswarrior]

Short jack.

Measure the jacking locations, front and rear, it has to get under there...

Many will have more than one jack style/size.

Air over hydraulic extends your working day, when doing maintenance.

Jacking, blocking and pulling the wheels off to inspect/grease etc, just getting the coach into the air is a whole day job for some of us... the actual work doesn't get done until the body returns to functioning after the jacking...

Happy coaching!
Buswarrior

[dtcerrato]

We all too good remember those days under a humid sky in the sand. Took 30 years (2011) for us to get the bus barn built. Now it's thanks to the pit, concrete, air-conditioned space, and the tunes... 

[chessie4905]

Love my pit. Wouldn't  have a coach without a pit.

[dtcerrato]

Heck not just the coach but everything goes on the pit! Golf carts, tractors, yard machines, all vehicles including the son's cars & trucks. It's just too easy not to!

[vintoolong]

Thanks all of you for your kindness.
I pulled the Pressure Protection valve under the pass side front bay.
It was completely stuck.
Part will be here in a few days.
Will see if that gets it done.
There is a theft prevention device on this bus that requires the step/chime light to be switched in order to hit the start solenoid. Is that something y'all(yes texan) are familiar with?

[lovetofix]

There is a theft prevention device on this bus that requires the step/chime light to be switched in order to hit the start solenoid. Is that something y'all(yes texan) are familiar with?

That is standard on buses built for Greyhound.

[buswarrior]

That is standard on buses built for Greyhound.

And many more, not exclusive to the dogbus.

Happy coaching!
Buswarrior

[plyonsMC9]

We built ramps for our buses out of 2x12s.  Didn't want to be under hydraulic jacks.  Jack stands also for safety.  Be careful!!!  If interested, I will post pix of the ramps.  Very easy to build.  Safety first!
Kind Regards, Phil

[lvmci]

Harbor freight has 20 ton bottle Jack's for a good price...

[chessie4905]

Get the air assist ones. One use and you won't want to use a regular one anymore.

https://www.harborfreight.com/20-ton-air-over-hydraulic-jack-95553.html

They make a 12 ton also for less. Watch for sales at a better price frequently.

[vintoolong]

Thanks for all of your advice, knowledge and wisdom.
I replaced the pressure protection valve today.
Everything pressured up and I found a massive leak in the engine bay where the intake pipe rubbed a hole in the metal air line that fills the tensioners.
Any suggestions on repair?

[buswarrior]

Cut it at the hole, install a compression fitting, job done?

Happy coaching!
Buswarrior