How to Release the Parking Brake On an IC CE With Hydraulic Brakes
ฝัง
- เผยแพร่เมื่อ 8 ก.ค. 2024
- Additional information: If the parking brake is set and the low brake pressure or low brake fluid warning lights are on, the parking brake cannot be released for safety reasons. In the event the parking brake has a problem, the service parking brake light illuminates and the hydraulic parking brake goes into backup mode and uses hydraulic brake fluid to maintain the pressure required to keep the parking brake off (in normal operation, the parking brake uses a special hydraulic fluid separate from the brake fluid). On the International 4300 or DuraStar Horton ambulances that have the Meritor WABCO HPB, the parking brake is a SAAR (spring applied, air released) type and will apply automatically when the gear selector is placed in park, just like its SAHR (spring applied, hydraulic released) counterpart. The reason for this is because the Meritor Wabco HPB system has a parking brake actuator that is designed to receive a special signal from the transmission when it is in park. Once the park signal is received, the parking brake will automatically apply regardless of whether the vehicle in question is equipped with a hydraulic parking brake or an air parking brake. Lastly, the difference between park and PB is that park uses an actual park pawl in the transmission, which is useful for if you need to disconnect the parking brake cable in order to move the bus in an emergency. In this case, the vehicle can still be secured using the park pawl until the parking brake can be serviced. PB, on the other hand, is a second neutral that is designed to automatically apply the parking brake. This setup works with both hydraulic and air parking brakes, including on some air brake trucks such as the Freightliner M2. In this position, the parking brake cannot be released. Only when the transmission is out of PB can the parking brake be released. In the case of this bus, it doesn't matter whether it has PB or a regular P position. Because of how the parking brake actuator is programmed on vehicles with the Meritor WABCO HPB, either P or PB will cause the parking brake to automatically apply, just that one setup has a park pawl (P) and the other doesn't (PB) so if you had to disconnect the parking brake, PB would not secure the vehicle, but P would.
To release: Ignition must be on or engine must be running, driver's foot must be on the brake pedal, and the gear selector must be in a position other than P or PB (if equipped).
Wow. This makes sense. I keep seeing buses for sale with the "yellow air brake" release but they state that they have hyd. brakes. This clears it up. I had no idea, thanks!!
Nothing beats an actual Air Brake System. Air Brakes are so much safer. I remember back in 1997 we had 20 AMTRAN RE’s from International with hyd brakes but it had an Air Parking brake, 1 gauge 1 needle and the yellow parking brake knob that was Air. Only thing we had on our busses that was Air was the door by.
I agree. And that's why I got trained on air brakes.
The former Marshfield bus service in my community had IC CEs with hydraulic brakes. The only air brake buses they at the time were 3 IC FEs (83 passenger)from 2000, and a 2002 MCI E4500 motorcoach. Most of the CEs were either 2008 or 2009 models and they also had a pair of CEs from 2005 or 2006 I think? All the CEs from the old company had the Maxxforce ce300 engines. They kept these for a long time until 2020 when a much bigger company, Kobussen Ltd. started serving our school district. All the new CEs that arrived a couple years ago, most are propane gas but about 9 or 10 of them came with the Cummins. I have no idea what the current company has for motorcoaches at that yard right now though, maybe a few MCI J4500s?
Interesting breaking set up that they've had over the years. I never knew that if your gearshift did have a parking position, I didn't know it would apply the brakes automatically.
Yeah a lot of drivers don't. The driver of this bus normally leaves it in neutral so they're most likely unaware of the auto apply too. Then when they try park, they wonder why they can't get the brake off (because it's still in park, lol).
@@BusMaster99 very interesting concept, I wonder why they even made it in the first place because all the drivers know the original instructions when it comes to applying the parking brake on the bus if it's hydraulic or airbrake.
@@JordanLoweElevaToursCanada It makes things easier because all you have to do is put it in park (or PB), but then when you jump in a newer hydraulic brake bus that has park, you have to remember to set the parking brake and then put it in park, otherwise you risk damaging the park pawl.
I prefer the diamond parking break
Thanks for the informative video! I greatly love learning about this system. I too prefer the WABCO to the older system that is currently used.
Yeah, I'm very disappointed IC stopped using this system in favor of a traditional hydraulic setup. Now there are lazy drivers who will put a wheelchair bus into park at either student stops or railroad crossings and not even bother with the parking brake, which means the parking pawl potentially takes a beating. This move is the very reason I stopped liking IC Bus, apart from the fact that Navistar previously sold trucks and buses with defective MAXXFORCE engines.
@@BusMaster99 I have to agree with you. They're also doing a facelift on them too, dont know if you have heard or not. Check out YT user Saftlinerc2, he has a video of the new look.
@@kodymcpheron5619 He and I had a falling out, because he attempted to invite his buddies into my discord server so they could start drama. But yes, I am aware of the new CE facelift.
And one more thing this is a good video
This is my favorite hydraulic brake system. I still don’t like that IC ditched it for the 2018 model year.
Honestly I think all school buses should have this system as it’s familiar to drivers who move from an air brake bus and I genuinely think it’s a good system.
Would you be able to get any recordings of just the pump motors running, like a static noise? I would like to use them if ok in some of my bus simulators...
Can you show us the Child Checkmate on a school bus where it sounds and talks as well. Thanks
Any tips bus master 99
Hello. Would you know by any chance on how to release parking brake on 2015 international IC. Hydraulic breaks kind. I did every option and still not releasing. Bus was sitting for 2 month before . Would you have any idea on how to release them ? Thank you
(It’s a short bus. And does have P option. )
Hm, you may have a brake system problem or a hydraulic line for the SAHR parking brake has started leaking. Check your brake fluid first, then let the brake system fully charge (brake pressure light should turn off). Then shift out of park and push the switch once the brake pressure light has gone out. If all else fails, you can cut the cable for the parking brake if you need to move it in an emergency. Just make sure it's in park and that the wheels are blocked.
I may not be a bus driver til 2032 because I have no driving experience and I have no driver license but I have to make a appointment with the dmv to get a driver's license
Uhhhhhhh if it’s stuck on parking brake how would a fellow disable it to get it over to a mechanic to actually fix it
There's a cable you can either disconnect or cut near the SAHR unit under the bus.
Are your bus fleet hiring for bus drivers and attendants
I'm not allowed to give the details of the barn I drive for, but yes, we are hiring as long as you're 21+.
@@BusMaster99 I'm 20 I may not be a bus driver til my late 20s early 30s if you are still hiring by then