| Author | Message | ||
| ChuckMC9 (Chucks)
Rating: N/A |
Not many of you modern bussers remember these things, but the *real* bus guys surely remember this item... ;) From da book's exploded view, it looks like the Clutch Release Bearing is built into a small assembly which has a hollow shaft, splined inside and out. Here's what I'm guessing, that the bearing assembly slides back and forth on the transmission shaft on the internal spline, and is connected to the driven discs on the outside spline. ? There's a thin (copper, brass?) ring which looks like it's on the inside race of the bearing itself, which is coming out and is visibly um, messed up. (it be broke) The mechanic discovered this during a lube job, and I plan to get it repaired immediately but am paranoid about driving it very much. All he said was that I should fix this 'soon' because eventually the transmission shaft would wear and things would get much more expensive. Should I drive it at all? Estimate is $1,200, including new discs and resurfacing flywheel. The price doesn't shock me, and I'm not beside myself with anguish like my silly little tantrum last year. Even though it seems to perform fine, I expected that the clutch would have to be dealt with one of these days. I know that a big part of the labour is removal of the transmission to get at the thing. I've read da book's explanation of the clutch, but thought I should ask if there's anything more I should know about the procedure or any comments you might have. As always, a grateful busnut. -Chuck PS: My Pop taught me on cars that the throwout bearing is at rest when the clutch is not engaged, and that one shouldn't keep foot on pedal any longer than necessary, in order to not abuse the throwout or the pilot bearing. I'm assuming the same is true on da bus? MC9 8V71N Fuller T-11605 ? (what da book says it should have) | ||
| Don/TX
Rating: N/A |
Your pop was PARTLY correct, that is true ONLY when the throwout bearing is properly adjusted. When out of adjustment, it can be engaged and turning anytime the engine is turning. | ||
| Brian Brown (Blue_velvet)
Rating: N/A |
Sorry about your woe$, Chuck. Have you looked into the cost of a used Allison? If you ever think you might want to join the slushbox crowd or have one for resale, now's the time to do it. Just a thought. bb | ||
| John MC9 Rating: N/A |
It'd make the bus easier to sell, too, Chuck. | ||
| ChuckMC9 (Chucks)
Rating: N/A |
easier to SELL?! Hah.  I'll add three tidbits in the way of answering my own question, since this topic seems to be rare in this crowd: - It's a good time to change the rear engine oil seal - The bearing comes from the factory *unlubricated* - it must be lubed after installation - Never use normal grease on the throwout bearing - must be hi-temp ...and changing to a slushbox + adding jake would probably cost as much as the bus is worth, but thanks for the suggestion. | ||
| ChuckMC9 (Chucks)
Rating: N/A |
Photo showing the insert, looking like its working its way out:  | ||
| Richard Bowyer (Drivingmisslazy)
Rating: N/A |
I'm curious Don, how do you adjust a throwout bearing? Richard | ||
| jimmci9 #2 Rating: N/A |
to adjust a 2 plate spicer clutch, depends on the type of adjustment the clutch uses... confused????.. some require a special tool..others use a 3/4" wrench.... the flat part of the throw-out bearing touches the "clutch-brake" to make the trnasmission input shaft quit turning (while you are stopped at a dead stop, so as to engage it in gear without grinding)...the clutch brake is a removeable spacer, that has brake lining fiber on it..... to adjust the 2 plate properly, you must first press the clutch pedal all the way to the floor... then using the appropraite tool, turn the "center section" of the cluch (which is the nut on the back of the trwo-out bearing) to achieve 7/16" of space between the throw-out bearing and the stop-brake (clutch brake)...and lock it down with the removable tab.... release the clutch pedal, and adjust it for about 1" of free travel.... mash the clutch pedal down again.... about 1-1 1/2" from the flor, you'll feel a "spongey " feel....this is the throw-out bearing making contact with the clutch brake....its now adjusted properly.... repeat untill you get these basic measuremnts...... | ||
| jimmci9 #2 Rating: N/A |
make sure that you get the 2 piece clutch brake when you have this redone.... in the event of its' failure, it can be replaced without pulling the transmission... the 1 piece requires a torch or chisel for removal (without removing the trans) | ||
| Don/TX
Rating: N/A |
Gosh Richard, Jim beat me to it! | ||
| Richard Bowyer (Drivingmisslazy)
Rating: N/A |
Thanks guys. Don't think I will ever have to do it, just wondered what the procedure was. Richard |