John T. and the bus

John: I can look tonight but my wife deleated some e-mail address and I don't know if yours was one or not. Anyhow I need to talk to you about your bus. A couple of comments. You said it was a single plate PUSH clutch, correct? Some bell housings have 2 sets of holes for the pivot shaft one for a pull clutch one set for a push clutch. To my meager knowledge, clutch brakes are only used with pull clutches. I will need to get some of my Spicer literature out. J.

No clutch brake or anything that looks like it would perform braking...........YES Single disk and dry and pushing the fingers (towards flywheel) retracts springs n pull pressure plate away from disc

I been cruising over on the Bus Forums and it appears LOTS of guys have the same problem on those old Spicers on 4104 busses. Those boards indicate the finger adjustment IS CRITICAL so Im takin them (prob Monday were takin a break) way back in towards the flywheel as when we got from rebuild shop even that is contrary to intuition as that puts them so farrrrrrrr from throw out in its rest full retracted position BUT we correct by adjusting big star adjuster on rod throw out arm to brung throw out up closer to fingers again

Its a 4 speed 1960 Spicer dry single action push clutch on a 4104 GM Bus

John T [email protected]
Thanks

A new clutch starts out with the fingers set to factory "spec", somewhat forward.

As the clutch wears, the fingers move rearwards toward the TO bearing.

If you start out with them too far rearward they will soon contact the back of the pressure plate assembly (as the clutch wears) and prevent the clutch from engaging.So starting out with them properly (and EVENLY) set is a GOOD thing.

I wonder how good your "lined plate" (friction disc) is.

If it is warped or doesn't run "true" with the hub it will drag and not release when the pressure plate backs away. In another post you were asking about how far the pressure plate has to back off to release the clutch. If the friction disc is good and true the pressure plate doesn't need to move much at all to release it.

If the TO bearing REALLY isn't moving the fingers as far as they need to go when the pedal is depressed it should be possible to re-do the levers that the release linkage attaches to... lengthen the one at the pedal and/or shorten the one at the release shaft to decrease the mechanical advantage and increase the "throw"... will take more leg power on the pedal but the clutch will release farther.

YEP, for sure Monday Im gonna start by resetting the fingers about paralell with the clutch where they were BEFORE I "fixed it" lol

We have also welded bushings farther down on the big bellhousing throw out arm which will yield more travel although harder on the legs.

If that dont fix it were GIVING UP hes gonna take it to Florida in a few weeks and knows some "real" bus mechanics down there.

On the Bus Boards a lot of guys with 4104 GM busses and Spicers have the same problem and they say to shift it into fourth then first helps

Thanks,,,,,,,,,, John T (have grown to hate big clutches)

I need you to rethink the bushings on the lever arm at the bell housing.
the farther out from the pivot the less throw you will have at the shaft.
the linkage needs to be moved closer to the shaft

I meant closer to the cross shaft (what did I say anyway lol) thats where we have welded some extra bushings for the long adjustment rod to pass through. That indeed yields more throw travel i.e. more cross shaft rotation, but it sure makes the pedal harder to push down. Its all that 30 feet of rods and pins and bushings and cross direction linkage that makes these darn busses harder then a regular truck pedal that goes direct to a cluth arm......

Once we get extra travel and re set the fingers WE ARE QUITTING as he has to go to Florida in a few weeks and will get "real" mechanics to fix it then, our "seat of the pants" shadetree method has met its limits lol

Thanks again John T