The left side jack was disassembled and cleaned.  It was discovered that the left side had been rebuilt with a new jack nut (similar to the three spare jack nuts in the RH machine shop).  This nut had been machined as is required to fit the bearing races on and fit the nut into the jack nut case.  The jacking case and lid also were machined to accommodate the different size rings for both ends of the nut  This rebuild may have been done after the jack failure that occurred in the late 70s / early 80s due to incorrect bearings and grease in the jacks.

There was less grease in the left side, and one of the worm bearings was on the dry side.  All other components still seemed lubricated, but not as much as the right side.  It seemed that some grease was stuck on the outsides of the jacking case and not mixing with the other grease.  The jacking case was approximately 70% full of grease.

There was a normal amount of wear visible on the surfaces of all jack parts according to Maico.  No unusual wear or colouration such as on the right side observed.  A leak in the shaft seal opposite the drive coupling was observed - this was replaced upon reassembly.

The jack was reassembled without grease .  The following measurements were taken:
Nut in jack case - vertical play:  0.008"  (vertical when installed)
Nut in jack case - tilt:  0.008"
Worm gear backlash:  0.017"

Nut on jack screw - backlash:  0.040"
Nut on jack screw - horizontal play on top of nut:  0.031"
Nut on jack screw - horizontal play on bottom of nut:  0.031"

The left side jack was fully reassembled with grease and is ready for installation.