Help with differential understanding/assembly

[erichill]

Working on a 1919/1920 (not sure) Chandler.  The car is in pieces, but so far has been complete.  I am trying to figure out the puzzles of assembling the differential especially the short shaft that connects from the driveshaft universal joint that leads into the differential housing and has the pinion gear mounted to it. Mainly how to adjust it for the slash in the pinion/spiral gear, and what the reason for the two sets of bearing shown in the photo come into play.  Anyone with a diagram, or who has worked on something similar would be of help.

The larger male thread screw into the front of the differential housing and is locked in place with a pinch bolt.

Eric

[PFitz]

The large bearing near the pinion gears is to take the radial load of the pinion gear shaft. The other set of caged ball bearings near the drive shaft end of the pinion shaft is to take the axial thrust load.

 

You thread the pinion housing into the differential housing to adjust how deep and where along the teeth that the ring and pinion teeth mesh. Same with how the ring gear is centered - sometimes by threaded bearing holders, sometimes by shims.  

 

You don't want the tooth load at the ends, or near the edges of the teeth - where they are weakest.

 

Using white grease as a paste to lightly coat the pinion's teeth, the grease will show where it gets wiped clean by the ring gear, thus showing the "contact patch" of the gear teeth.   Ideally the load contact patch should be near to center on the teeth as possible. 

 

You also don't want the gears to mesh too tightly.  Typically about .005 to .006 of "backlash" play - movement in the ring gear before the pinion moves. 

 

Paul

Edited July 23, 2017 by PFitz (see edit history)

[Guest]

Just a generic pattern chart.  May be of some help.