Tom,Quote:
Originally Posted by truk4u
Cruise control ?? These things have cruise control ??
WOW!!
I knew there was a reason I wanted one !!
Michael
:D :D :D :D
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Tom,Quote:
Originally Posted by truk4u
Cruise control ?? These things have cruise control ??
WOW!!
I knew there was a reason I wanted one !!
Michael
:D :D :D :D
Ben,
The tipped over coach is 589, a 2000 "H", an HWH 2 slide equipped bus. It was being used in Alaska on the "Extreme MakeOver TV show and was being driven back to the lower 48,
Up to this show segment, Marathon had provided the driver. This time, it was not a Marathon driver. We heard several differnet stories as to what exactly happened. A Deer, soft shoulder, driver error, whatever it was, the service crew said once the insurance thing is hashed out, the coach rebuild was a future winter project.
Glad you are making it to SF. It was 73 degrees here in the Front Range today. Heard they had snow flurries north of Leesburg, Fla.:D
Happy Turkey!
Michael,
Yep, we got em, what are you waiting for?:p
With all due respect, I have to disagree with your braking suggestion of slow, steady pressure. That is exactly what will cause fade and a trip to the dirt or WORSE. Being a trucker for the last 40 years (ya I know, I'm getting old) I have watched smoking, fading brake drivers get in bad situations. I think the buses are much more prone to this problem without the jakes, as the brakes pretty much suck from the get go. I'll take 80,000 lbs and five axles anyday downhill, provided the brakes are adjusted, rather than the bus. Maybe it's because of a combination of drum on the drive, and disc on the steer and tag, I'm really not sure.
For those not familiar with the Commercial Drivers Manual, here is a piece from the Proper Braking Technique:
Remember: The use of brakes on a long and/or steep downgrade is only a supplement to the braking effect of the engine. Once the vehicle is in the proper low gear, the following is a proper braking technique:
1. Apply the brakes just hard enough to feel a definite slowdown.
2. When your speed has been reduced to approximately five mph below your "safe" speed, release the brakes. (This brake application should last for about three seconds.)
3. When your speed has increased to your "safe" speed, repeat steps 1 & 2.
Tom,
I like you have a long history with trucking (also like you, longer than I care to remember). I can tell you that "my" method had worked for me until Jakes became commonly installed on trucks. At that point going downhill was much easier. I can still remember "setting" new brake shoes with a good long downhill.
I agree with everything you say. However one can find themselves in trouble no matter which method you use. Going downhill is a carefully thought out mixing of weight, speed, grade, length of grade. You know that the "bad situation" you find yourself in at the bottom was caused by decisions made at the top.
If one uses the now taught (there was no teaching in the "old" days-except by veteran drivers :D ) method and you start down a hill too fast the results will be no different.
About buses, I've just started reading all your complaints about braking. Thats interesting. It seems a common complaint in the MH world. Tom is right about taking 5 axles worth of brakes and 80,000 pounds with a Jake and running hills. It's a no brainer (well for most anyway). But that said, I find the weight of most MH's is just barely above that of an empty truck and empty trucks are a snap to get down hills.
My current coach is just below 40,000 pounds with the toad. I can flip on the exhaust brake, and let it ride down the grapevine (I-5 north out of LA - 5 miles of 6% grade) and NEVER touch the brakes. It will hold 53-55 mph all the way down.
I-5 north coming down into Ashland Or., same type of hill only a little longer and has some parts that are steeper than 6%, I hit the brakes 4-5 times lightly to trim off speed in those sections. (the stabbing method ??)
Your buses weigh more but Jakes create more braking power than the exhaust brakes. Net even ??
Michael
Still has a CDL (and actually got to use it last Tuesday !! Yeah !!)
They don't let me out too often in a truck anymore...:(
Happy Thanksgiving to all !!
We're bouncing around a little here, but it is all related because if Ben doesn't have supplemental braking like a jake or retarder he has to pay attention to advice like Tom's. Tom also brings up a good point and should be added to help Ben with his problem.
The cruise control may or may not be a part of the problem. I think Ben has to rule out the mechanical aspects by powering the solenoid valves with the bus idling. I find it very difficult to imagine both solenoids failed at the same time, but it is possible one has failed and Ben was unaware, and when the second one failed he realized there was a problem. If they are functioning then Ben needs to look at the controls, and Tom is correct in suggesting the cruise may be a factor.
I hope JDUB can jump in here, but if my memory is correct, DDEC can be programmed to allow the use of the Jake with the cruise engaged, or to prevent the use of the Jake when cruise is engaged. That provides another point to look for a problem. I don't think flashing the codes would tell Ben anything on this, but a DDEC reader may give some clues.
If it's anything like my jake issue (8v92), the DDEC required a zero throttle signal, and then it would send the signal to the jakes. I don't have the schematics in front of me, but we could measure (on mine) 12V at two lugs in the electrical panel (under the driver), and again back in the electrical panel above the engine. In my case, the signals made it all the way to the back electical box, but the spades had been removed for an engine service, and forgot to be replaced. Doubtful that's Ben's issue, but I'd be more than willing to see if I can get the terminal numbers from my manuals. Might be the same on Ben's unit.
I think the terminals are specific to a particular coach. The Prevost guy I spoke to when chasing my problem said they are usually X and Y, but when he looked up my serial number they turned out different.
Jon is correct in that the codes related to the Engine Brake are cruise control specific.
If the CEL (Check Engine Light) or SEL (Stop Engine Light) are functioning correctly and there is no indication of a fault, then it is unlikely that the issue is anything other than a wiring harness or fuse problem.
As the Jake Brake is an added system to the engine, the DDEC only seems to deal with it as a function of Engine Overspeed (Engine Brake Engaged) or the Cruise Control (setting it up to keep the Jake Brake from coming on when you are following Anal-1 thru the hills in South Florida with the cruise control on :eek: Hey, I'm not making this up :rolleyes: )
[SIZE="3"]Ben, Was there ever a conclusion to your Jake Brake issue?[/SIZE]
It worked fine the next day and has ever since. I think I just needed to re-boot the coach... shut it down and start it up again... I happen to keep it running all day while driving from OR to CA.