LP2a SAR restoration

[Phillip]

Thanks Dale & Ron,

Colour is hopefully Khaki Green No.3. I do have a NOS part in matt green with the colour being close enough, especially once it fades.

Diff is pulled apart. The axles had been removed at some point so I was not expecting good things once the diff was opened up. In this respect I was not disappointed as ,despite there being plenty of petrified oil, the pinion is quite worn and at some stage the crown wheel has dropped bits on a few teeth.

As this carrier was fitted with the muff coupling, I want to keep it that way. I had thought that this was the last style of the three couplings but after research on the web, it seems that this ten splined pinion was late 30's and according to the hot rod forums, hard to find

Other that the crown wheel and pinion, the rest of the diff is very good, I'll throw a complete set of new bearings in there whilst it's all apart.

I'm also a little perplexed by the brake hub springs. It seems also that this four spring configuration was unique to 1938. Consequently there is very little information on the return springs and I can't locate any modern equivalents. Any ideas?

[Lynn Eades]

Phillip, Is this a 5.83:1 ratio? (Ratio stamped into housing)
Do you have a book to cover the rebuild?
What were the bearings like?
If you dress up the teeth will it run again?
Basically the 38 axle with splined pinion was fitted to the LP2 Carrier.
The LP2A was fitted with the 1940 axle with a keyed (taper) pinion.
The parts book lists those carriers fitted with the 5.83 ratio. This affects the speedo as well. These carriers were built after Jan. 42., with 1938 pattern axles.
There a two types of 1938 type one and type two. These variations relate to the way the axle tubes mount in the hull. type two requires no sleeves in the mounting brackets.
Notes: make sure you get your pinion preload right.
Heat the housing to load your pinion carrier in.
The side bearing preload is set by the gasket thickness (only one size 0.010"- ten thou.)
Any questions ask.

[Phillip]

Hi Lynn,

Thanks, one of the first things I look for before beginning a restoration is the manuals - it generally saves a lot of errors (but then being slightly impetuous creates a few as well). I do have to remind myself that, soldiers being soldiers, and the army being the army, equipment changes when finally in service.

I have four manuals - still missing page 13 from "List of Spare Parts" to anyone reading (hint, hint).

The spare parts catalogue (Section E, Page 1) draws reference to 1938 diffs fitted to carrriers post 01JAN42 so I assume these are LP2a not just LP2's. It also lists two ratios 5.83 and 6.66. I cannot locate a stamp on the diff housing but sand-blasting may reveal this later. Ratio is 6.66.

Fittings on the diff housing are 1938 Type 1. This carrier post dates the manual SN's for fitting of this axle - (does anyone know how to date carrier SN's?) so given that all the parts match, it is highly probable that this diff is correct for this hull.

Another strange aspect is the offside front guard, sand blasting revealed that this had the holes for the front guard mounted data plate welded up. A case of SAR or the ADF using older stock?

[Lynn Eades]

I guess when the troops wiped out a few front guards, the powers that be saw the error of fitting the data plate to the guard and ordered the change.
Once the order went out (which may have included instructions to weld up holes) then the old stock guards would have been still used.
It was a time of no waste. I have 3 years of army council instructions. one item covers the recycling of old rubber bands and the return of the worn bits of rubber from old pencils!