| Author |
Message |
evacuated from mississippi
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, July 09, 2005 - 12:14 pm: | |
I have discovered on my Mci9 a DUHHHHHH valve. This valve is a part of the brake system. I kept reading the manual on my brake system since I could not get it to release prior to evacuating. The push pull valve was working fine but the emergency brake was not releasing. Da-book said "manually release brake" well I pushed and pulled and pushed and pulled. Nothing was allowing the bus to move. I saw somthing in the floor under the brake so I bent over to pick it up. In the process I pulled up on the brake pedal. The bus was still in gear and the brake valve was released here goes the bus moving out of the rv slip. I got the bus stop prior to it pulling all the wires and plumbing out. I then went back applied push/pull valve and released it, the bus was no longer locked up.
Now I am confused so I go back read da-book more found a spot that says do not touch brake pedal when the push/pull is applied. If you do you have to manually release the brake. Dang I really did not know that meant physically pulling up the brake pedal.
I applied the push/pull touched the brake boom system is locked rock solid. Lean over pull up on the brake pedal and it released with no problems. To think da-book could have said "hey dumba$$ bend over and pull the pedal up". |
Dave Wheat
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, July 09, 2005 - 12:39 pm: | |
I've driven many MC9's and never had to physically bend over and pull the brake pedal up. We released the "push/pull" and then somewhat forcefully push in and release the brake pedal and the bus is free to go. Try it. |
evacuated from mississippi
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, July 09, 2005 - 12:47 pm: | |
I did, That was the normal way I have used over the years on different buses. This was a first. Apparently if someone applies the brake when the bus has low pressure this application sets emergency brake. The only release that worked was the one described. |
evacuated from mississippi
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, July 09, 2005 - 12:49 pm: | |
This for the record is a NJT. Maybe it was a extra safety feature of this bus. Regardless NOTHING worked prior to this simple action and I could replicate the problem and resolve with the same action. |
David Hartley (Drdave)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, July 09, 2005 - 7:09 pm: | |
Brake pedal is sticking.
Mine does the same thing since I washed out the interior. Have to get under the spare tire area and lube all the fittings. |
Robby
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, July 11, 2005 - 8:21 am: | |
Dave is correct, I run a fleet operation. Every now and then on older MC-9's will have a brake release problem. The issue is the application valve and then rod itself that goes through the floor gets stuck. Spray the lube on the rod and it seeps through the floor to the valve. Work it up and down several times and wha la it's free! |
evacuated from mississippi
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, July 12, 2005 - 3:40 am: | |
Not arguing with anyone but this is rather strange. I tried this a couple of times to see if I could do it. First I applied the brake after the air dropped to zero with the push/pull applied. Locked up, raise pedal to release. Applied brake after the air dropped to zero without push/pull applied, when I started the bus and air was built up brakes were locked, Pulled brake pedal up no change. Applied push/pull then released push/pull no change. Then reapplied push/pull released and pulled up on brake pedal no change. Reapplied push/pull released push/pull and applied pressure on brake, Brakes released.
Applied push/pull turned bus off before pressure dropped, applied brake. When doing this the bus was now locked up would not move when I released push/pull no matter what I did except when I pulled the brake pedal up, then it released fine.
To test the lube issue (hanging up) I sprayed wd40 liberally. Retested with the exact same results. So I do not know what or how it is supposed to work other then the fact nothing works except this if the brake has been applied when the push/pull is applied. |
DavidInWilmNC
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, July 12, 2005 - 1:39 pm: | |
To release parking brakes, aren't you supposed to have to
1) air up the bus
2) push in the knob
3) push the pedal and relase it (in your case, push the pedal and pull it back up)
If so, then your statement "Reapplied push/pull released push/pull and applied pressure on brake, Brakes released." would seem to be how they're suppose do work, according to MCI.
Check this link www.mcicoach.com/parts-service-support/serinfo/serinfo0700.htm It might be part of what's happening to your brakes. |