110 Salisbury Rear Axle (Part 1)

I have started in earnest on the 110 rear axle for the conversion.  The first job was to clean it up, which consisted of a good wash, removal of all of the suspension brackets (including the damper and anti-roll bar brackets) and a long session with the angle grinder and drill wire brushes.

Next was replacement of the pinion oil seal, which showed evidence of a slight weep (not bad for such an old axle).  This is done by carefully marking the pinion flange nut and the pinion shaft end and counting the number of turns to unwind the nut.  Once removed, the flange is tapped off with a soft mallet and the seal and paper gasket removed.  A suitable drift is required to fit the new seal or it will be distorted – I found that a spare connecting rod big end from my broken 19J engine worked well.  The inner bearing benefit from a clean our before the new seal was refitted with a bead of RTV sealant around its edge.

Unfortunately, the nut alignment marks washed off during cleaning of the parts, just prior to reassembly.  A bit of research revealed that the crush tube between the two pinion bearings needs 250’lbs on the big nut to start shrinking, and progressively more to continue until the correct bearing preload is reached.  I decided to try 150’lbs on the nut, which should be enough to tightly close the bearings against the crush tube but not shrink the tube any further.  Removing the axle’s half shafts then allowed me to compare the combined pinion and diff carrier preload against that of a part stripped 109 Salisbury axle.  The readings were identical, so I’m satisfied with this solution.  The rear cover was removed from the diff housing to check the general condition of the diff.  It’s clean with only a tiny (about 1/4mm) chip to the edge of a crown wheel tooth, and the diff backlash is well within factory tolerances.

Following that, the diff housing was given a clean with brake cleaning fluid and a spray of Zinc182 primer to prevent reappearance of the rust.  The brackets for mounting the brake lines were removed for this, as was the reinfocing strip along the bottom edge of the rear cover plate.  The cleaned hub drive flanges have also been checked and sprayed with the same primer.

I have removed the hubs and drum brake assemblies (the same as on a 109, except for an additional mud shield around the rim of the backplate and drum lip).  These have been set to one side while a test fit of the brake calliper brackets was made – these will permit the fitting of a pair of Discovery 200Tdi (amongst others) callipers and hubs to be fitted at the rear to allow the disc brake conversion.  I am hoping to take delivery of the Discovery hubs and brake parts soon as a swap for some unused parts.