BCM Community

Hey all, now that the weather's getting better I'm acquainting myself further with my still-pretty-new-to-me 4104.  As many others are familiar with, these beasts along with many others have unusually tall first and reverse gears, which can make maneuvering precisely into a parking lot or around obstacles tricky (mine seems to want to go 10-15mph on the flat with the clutch out at idle).  So I figure I'd be better off asking now before I settle into bad habits, what do the rest of you do in these situations?

Mine is horrible backing up if there is a hill involved. I try my best to plan things out so that I'm backing downhill and not uphill. For instance, if I'm making a 3-point turn, the first leg will be forward uphill, then reverse downhill. Not always possible, so if it's necessary to back up a grade I've got to give a little throttle before letting out the clutch.

I was taught not to slip the clutch. So, if I have to use throttle to get going I try to do it as swiftly as possible and not dawdle with the clutch slipping.

Maneuvering forward, I can creep along pretty slowly in 1st gear. If you can't, then perhaps your idle is set too high. If you're idling forward 10-15 mph I'd check the idle speed - my at-idle maneuvering speed is much less than that.

At times when I am maneuvering in tight quarters, like a campground, there are times when a short clutch engagement is all that's necessary to get moving, and then I'll coast the rest of the way.

Biggest lesson I've learned is to think through things so that you're not in these situations any more than necessary. Took a while for me to keep in mind that I was driving a bus at first, especially when parking. After a few problematic/tight situations like that, I learned to park so that it was easier to get going again. I'd rather walk a few hundred yards extra than burn out my clutch because I wasn't careful parking.

Rob which ratio differential do you have in your 4104?, the 411 or the optional 356 - it makes a big difference...
I'm not sure what my idle speed is in first but 10 to 15 mph sounds kind of high! We run the 411 differential.

Sounds like the 3 5/9. With 4:11, only backing up on a grade should be a little bit of a chore. Assuming engine is in decent condition with a proper tuneup.

It's entirely possible I'm overestimating the speed - until I get the new rubber on, I'm only moving it around a barnyard for maintenance purposes, and everything feels faster when you're riding 12 tons of metal around enclosed spaces.  I've mostly been using the 'clutch pulse' method so far - let the clutch out then right back in to get a bit of speed when needed, mostly coast to where you want to be.  Just wanted to make sure there isn't a better way, as I want to be as kind to the drivetrain as possible while still getting done what needs getting done.

Soft ground?

Depends on the weather, but I won't drive it if the ground gets too soft.  I've quickly gotten into the habit of parking on boards if I've got to let it sit a while, I was barely able to escape the ruts I made from sitting all winter.

Excellent, always on boards if it isn't pavement or cement.

Especially an old GM with a clutch.

No sitting ruts allowed!!

My new bus is getting treated to a set of new 2' x 2' boards.

Happy coaching!
Buswarrior

Back when I was a fueler/cleaner/hostler, later when I was an operator, it was always clutch in-clutch out; never slip.  Out to get moving, even if it wasn't fully engaged, then immediately back in and coast.  Engine at idle.  That was the method on transits, suburbans, and coaches -- all diesel and possible at idle  because of the high torque. 

Schoolbuses with gas engines forced some slipping because of their lower torque, but still every effort made to minimize clutch wear.  Private, family owned bus company, every asset treated carefully (by most) because it was private money that owned the equipment and paid for repair -- and also paid our wages out of what was left.     

Arthur