Author Topic: Runaway bus?  (Read 6541 times)

Offline RJ

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Re: Runaway bus?
« Reply #15 on: November 02, 2017, 06:33:13 PM »
Long ago, there was a pair of videos... I did a GM 5307 transit, another busnut did their coach, before and after "adjustments"...

Crumbs, who was it? And where did it get posted?

Buswarrior -

Here's the beginning of the thread you're looking for:

http://www.busconversions.com/bbs/index.php?topic=1489.0;wap2

All the "newbies" who haven't been around since this thread was initially posted should take the time to read the whole thing, all 16 pages, plus the link to the blogspot article that has even more information.

I'll talk to Brian to see if he's still got the video. . . stay tuned.

FWIW & HTH. . .

 ;)
1992 Prevost XL Vantaré Conversion M1001907 8V92T/HT-755 (DDEC/ATEC)
2003 VW Jetta TDI Sportwagon "Towed"
Cheney WA (when home)

Offline buswarrior

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Re: Runaway bus?
« Reply #16 on: November 02, 2017, 06:55:53 PM »
FOUND IT!!!

https://www.youtube.com/watch?v=EOx7J2_qetU

Yeah, baby, the power of group memory and Google!!!

From the history, note the follow up:

buswarrior:
A word of caution from later posts.

The video is resident elsewhere, perhaps someone else remembers where?

After the video shoot, from the large difference in results, Brian's brakes were found to be contaminated by way of leaking wheel end seals, thus, its stopping distance was far longer than it should be.

The evidence, as recorded in the video, could be re-packaged to serve as a warning as to what happens to your ability to stop if the wheel end seals are leaking into the brake drums.

He tore down the wheel ends shortly after this thread, discovered this, and fixed it all up.

No matter spring or DD3 systems, when everything is up to snuff, they all stop much the same, with a transit coach having some advantage due to the larger swept area of the brakes installed for the constant stop and go.

So, take your coach out, ensure all is secure, which you should be doing every time it moves anyway, and give it a whirl!



happy coaching!
buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline Bus Lurker

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Re: Runaway bus?
« Reply #17 on: November 02, 2017, 09:38:45 PM »
Getting back to Don's original question, is possible for the tag axle to have more air in the bags than the drive axle, thus reducing the traction on the drive axle?  The steering axle and tag axles don't have DD3s or Maxi Cans, do they?  Do any of you have a manual adjustment for the air in tag axle bags?

Mike

Offline TomC

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Re: Runaway bus?
« Reply #18 on: November 03, 2017, 09:11:34 AM »
Complete driver error. The driver should have released the lift axle when unloading. You're parking brake should be such that only a bull dozer could slide the bus when applied. Good Luck, TomC
Tom & Donna Christman. 1985 Kenworth 40ft Super C with garage. '77 AMGeneral 10240B; 8V-71TATAIC V730.

Offline luvrbus

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Re: Runaway bus?
« Reply #19 on: November 03, 2017, 10:10:46 AM »
The newer buses have the spring parking brake on the tags also now,the dd3 chambers were notorious for not latching tight when the adjustment was off just a little bit
Life is short drink the good wine first

Offline windtrader

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Re: Runaway bus?
« Reply #20 on: November 03, 2017, 12:08:50 PM »
RJ - link not working, got an update?
http://http//r4106.blogspot.com/2006/08/intelligent-dumb-question-answered_10.html

I am nearly certain what the driver said indicates a driver error. He should have taken pressure off the tag axle before unloading the wood. People heard squealing so the drives were locked and did not fail. When the truck has some amount of wood taken off, the drives lost just enough traction to get it skidding down the pretty steep driveway. He said he never had that happen before. First time for everything; I'm sure he'll remember in the future. LOL
Don F
1976 MCI/TMC MC-8 #1286
Fully converted
Bought 2017

Offline HB of CJ

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Safety Precautions ...
« Reply #21 on: November 03, 2017, 12:44:40 PM »
I for one can not believe the wood truck driver did not take the most basic safety precautions if he parked that truck on that steep of grade.

Multiple chocks.  Lowest gear in Tranny if manual.  If an automatic then there you have it.  We used heavy safety ROPES tied off to something anchored.

Rope that puppy off.  The driver should be fired.  Then sent back to drivers school.  There is no excuse NOT to conduct basic SAFETY considerations.

Offline B_K

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Re: Safety Precautions ...
« Reply #22 on: November 03, 2017, 01:46:56 PM »
I for one can not believe the wood truck driver did not take the most basic safety precautions if he parked that truck on that steep of grade.

Multiple chocks.  Lowest gear in Tranny if manual.  If an automatic then there you have it.  We used heavy safety ROPES tied off to something anchored.

Rope that puppy off.  The driver should be fired.  Then sent back to drivers school.  There is no excuse NOT to conduct basic SAFETY considerations.

If the truck was a manual transmission it would have been impossible to off load w/o power take off running so the driver would have to leave running in neutral in order to unload. But he should have unloaded the tag axle prior to setting the brakes.
;D  BK  ;D

Offline buswarrior

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Re: Runaway bus?
« Reply #23 on: November 03, 2017, 03:14:04 PM »
In a coach with a 6k rated tag axle, if the tag has enough pressure to unload the drive axle, structural failure of the tag bag mount will be imminent. They can't take that kind of weight.

The newer 45 footers, the tags have become rated pretty much the same as the steer axle, and you know it, when trying to start out in slippery conditions, or the drive tires hit the painted stop line at the intersection as you pull away.

When this hobby goes from single circuit service chambers and a hand brake parking next to a current 2 axle spring brake system, there are a lot of "it all depends"... add in some crazy maintenance, or lack there of....

Not a bad idea to have a proper set of chocks for your coach, and use 'em?

happy coaching!
buswarrior


Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline HB of CJ

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Re: Runaway bus?
« Reply #24 on: November 03, 2017, 04:30:52 PM »
B  K :  if the driver had to engage the power take off to dump that load of firewood, why in the world did he snatch defeat from the jaws of victory and spot his load in such a high grade situation guaranteed to fail... from the get go?

This makes it worse.  Not only should he be fired for being stupid and dangerous but he also should be made liable for any damage his stupidity resulted in.  No excuses.  But then again we are not dealing with reality here.  Only stupidity.

We used to lump, (move) furniture in San Francisco.  The very hilly parts of town then actually had special dedicated cleats intended to tie off heavy trucks soss they did not run out of control down hill.  Common sense.  Long ago.

Offline RJ

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1992 Prevost XL Vantaré Conversion M1001907 8V92T/HT-755 (DDEC/ATEC)
2003 VW Jetta TDI Sportwagon "Towed"
Cheney WA (when home)

Offline windtrader

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Re: Runaway bus?
« Reply #26 on: November 04, 2017, 11:32:15 AM »

Thanks Russ,

Great info. Adding to the annual inspection process, one of the busses I looked at was being sold by a Bay Area tour operator who mentioned how thorough the mechanics check out the busses. I believe he said it takes two mechanics the better part of a day to do the inspection.

He said there was no specific charge for the inspection but it is baked into the fees the state gets for licensing commercial vehicles, some goes to to DOT for this inspection.

One thing for certain is in the very unlikely event I buy a currently registered Calif commercial bus for a conversion, I'll surely have the mechanic doing the bus survey to skip all the safety related checks.
Don F
1976 MCI/TMC MC-8 #1286
Fully converted
Bought 2017

Offline buswarrior

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Re: Runaway bus?
« Reply #27 on: November 05, 2017, 07:53:29 AM »
Only a day, for "an inspection" ???

Long ago and far away...

The annual took 2 mechanics for 5 days to go through an MC8-9-102A. There were lesser levels at other time markers, from daily on up to 6 month.

Pages and pages of company written inspection and preventive maintenance procedures, blending the manufacturers' content with all that stuff that isn't written down. Every moving part was involved, either tested, inspected, lubed, adjusted, whatever...

80 hours of labour annually, 4 hands working together.

Reliability comes from familiarity, inspection, and replacing/adjusting/repairing before failure.

Every busnut needs either a pneumatic or battery powered grease gun... that which is hard to do, won't get done...

How many hours does a busnut spend on pure inspection/preventive maintenance each year?

happy coaching!
buswarrior

Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

 

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