Triumph Repair: Differential on spitfire 1500, stub axles, spitfire 1500

Question
I am trying to restore a 1973 spitfire 1500 4 speed no OD. I am replacing the pinion oil seal, bearing and gasket between the casing halves. I unbolted the differential casing and removed the oil seal but cant get the casing to come off. It appears the bearing prevents the casing from coming off but I cant get to the bearing with any of my tools to remove it. I was afraid to pry to much on the casing. Does the bearing have to be removed first.

Answer
Chuck,

Changing the pinion bearing requires a differential case spreader, basically a tool to stretch the diff casing slightly to allow the carrier bearings to be removed/replaced.

In order to split the casing halves you need to first pull the side axles (stub axles) out from both sides.  They're held on with 4 allen head bolts (each side) that you get to by aligning the odd shaped side of the stub axles with the bolts.  It's easier to understand with the diff in front of you.

Once the 4 bolts are removed on each side the stub axles are just held in by friction on the stub axle bearing races in the diff casing.  Gently pull on the stub axle to remove it.  Don't pry on the flange that holds the oil seal or it'll crack.  Don't ask how I know.  :(

From experience I was able to replace the pinion seal on my '73 1500 by removing the drive shaft flange and drilling two small holes into the metal part of the oil seal.  Screw two wood screws (self tapping) into the holes and you can use vise grips to grap the screws and pull the seal out of the differential.  That was when I figured out that removing the differential carrier was required to get to the pinion bearing and it was beyond my tool kit at the time.


Cheers,

Jim