MCI Parking Brake Question - Update

[Busted Knuckle]

You must do a lot of driving to wear out the brakes in five months.

Well maybe and maybe not!

OK Paul first don't think I'm picking on you, or saying your stupid or something here.
But so many times I see folks who drive these beasts that have not been around them for yrs who have no idea the proper way to release a set of DD3's. And many times will brive them all over the place with them partly still on. Which in turn wears them out faster!

OK that said the proper way to release DD3's is to let the bus build air up to the max pressure (spit off).
Then Depress the brake pedal while pushing down on the brake release button. Once the button is down push the brake pedal all the way down for 3-4 seconds then release. The brakes should now be completely released. Failure to do this properly can result in one or both of the brakes staying partly or even completely engaged. While most times it is noticed right away by a seasoned driver, sometimes drivers not used to buses or that particular bus will think "man this thing is a dawg!" And not knowing it will be working the engine & trans HARD but still able to drive it!

OK now that said, it also does not say that it is Pauls problem here either!
It could be that ABC told Paul the brakes were good to go when he bought it so that the cost of repairs didn't scare him away and cost them a sale. (once he owns it it doesn't matter what it cost to fix it, because they done sold it!)

SO it could be either of these or it could be something all together different too!

Paul good luck and let us know how it turns out!
  BK 

[DaveG]

Thanks Bryce, you have accurately shown/described both sides.

[buswarrior]

Another great reason to install a "Brake Inspector".

Monitors the brake stroke, on every application and release, from the driver's seat you know if they came on, you know if they are within adjustment, and you know they fully released.

Busnuts and sticky brake parts go hand in hand....

On sale until the end of the month from the Canadian distributor for $450 CDN. Reg price is $699 or something like that.

http://www.spectra-ssa.com/ and click on the video part way down.

I am a customer, no other benefit to me, blah blah blah.

I wonder in an age when they have regulated tire pressure monitoring in the new cars, why electronic monitoring of brake stroke continues to be ignored, when brake adjustment continues to be the number one commercial vehicle defect by a long way?

happy coaching!
buswarrior

[paul102a3]

BK,

No offence taken on your comment. I was taught the correct method to release the parking brakes from a long time driver and I have added an additional step to help me make sure the parking brakes have released.

When leaving from my driveway, I release the parking brake while the transmission is in neutral. I then let gravity roll the bus for 10 feet or so then apply the service brakes and shift into forward or reverse. I have a very slight slope to my driveway so if the parking brakes did not release, I am pretty sure I would know it.

If I am on flat ground, I follow the same procedure as above except I bump it into and then out of gear to make sure the bus will roll. 

While this in no way guarantees the parking brakes have fully released, it is one more step that can alert me to a potential problem.

After reading your post, it struck me that I would not have a leg to stand on with ABC bus. I cannot prove that I did not cause the problem. On the other hand, they have a document stating that the brakes were fine when I left the shop.

Buswarrior, thanks for the info on the "Brake Inspector". It looks like a nice system and would give us some good feedback.

Paul

[bevans6]

I too worry about the parking brake not releasing and make sure the bus can roll freely.  Of course, my driveway is a slope, so that's easy for me, but still an easy check.

When I bought my bus, the owner said the brakes would pass a DOT inspection but would probably need replacing soon.  My deal was new shoes all round and a thorough inspection.  when I got it, it had the new shoes but the front slacks were so badly adjusted the cans stroked out.  so the link to a stroke measurement system is ideal!

Brian

[JackConrad]

Not a guarantee, but when I release the brake and put the car in gear, I expect it to roll with no throttle application. 

[paul102a3]

Final Update

Drive axle shoes were replaced along with new oil seals installed. Cams, bushings, cans, adjusters, etc were fine and did not need to be replaced. Drums were in excellent condition with very little wear. No evidence of overheating from dragging the brakes.

Shop believes the wear on the shoes was normal wear and tear which makes me feel better since I have been beating myself up thinking I may have not allowed the parking brakes to release.

They did find one of the devices that locks the adjuster screw on the slack adjuster was not engaged so that did not help matters.

All the brakes are now adjusted and working correctly.

I am a very happy camper.