24V CAV starter refurbishment questions

Finally yanked the starter after nothing but cicada-like sounds when the starter button was pushed.
Needing an adventure (at the age of 74) I removed fender, heat shield, and dropped exhaust pipe in order to reach through a goopy mass of oil and tar to bolts and cables. So much fun, so little time. I have decided this is a bourbon project, not a beer one.

Lo - the studs backed out of the flywheel housing easily, and I can ease (drop) the starter between the frame and the floor into a carboard box.
Upon inspection, there was only one 7" bolt holding the starter ends together...yikes. Things area bit loose. I lift and tied up the brushes with cable ties, removed the one remain 7" bolt, and eased the rotor out of the casing. Commutator is a bit pitted, but not work. No electrical smell. No solder thrown everywhere. Front bushing seems a bit wobbly. I'll check continuity on the windings, but things looks intact.

After carefully removing a bit (well, a lot) of tar from starter, it reveals it's a CAV unit.

So:
A. - What's the story on CAV starters? Were they in cahoots with Lucas or just an alternative supplier to Rover? Were they just a supplier of FFR parts?
Are there any parts interchangeable?

B. Anyone got a 7" threaded rod/bolt to replace the missing one? Used is fine.

C - Are there any shops in the New England area (or maybe beyond) who will rebuild this grease and tar sodden specimen or do I need to get a new/refurb unit from gwd knows where. I'm looking for suggestions and experiences here.

D - Am I now at the point where it's more cost effective to convert to a 12V system?

Many thanks for constructive advice.

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Attachment 13710

I cannot remember where CAV originated but by the time yours was made it was part of the Lucas empire . Most Diesel & truck parts ( which are usually 24 Volt) were manufactured under the CAV brand. The Diesel parts (injector pump, injectors, filter etc ) on Series Land Rover were all CAV. Normally it was only Military Land Rovers that had 24 volt systems, and of course FFR LR's were 24 volt.

Greetings, and I like the its a Bourbon job as opposed to a beer job. I purchased MOD 1965, 2a years ago that was converted from 24 volts to 12, wiring harness shot, ripped to shreds. When I decided to completely restore truck, I decided to go 12 volt, two reasons, hard to find and expensive 24 volt parts, and just ease to diagnose. Just my 2P. But I remember the Tar layers, and shoddy, broken motors, and bits. Check with an experienced electrical rebuild shop, they might take on that starter to rebuild. Cheers, and best of luck

Starter adventure - update:

Executive summary: It's ALIVE!!!!

Backround:
The problem, as usual, a combination of factors, including an Optima battery that showed 12+ volts across the terminals but had no uuumph. Being in-series (we're talking a 24 volt system here), there was enough power to trigger the solenoid, but not kick in the starter. The only way I found it was when I tried to bench test the starter. doh.
The battery was still under full warantee, so a free replacement.

The starter looked sketchy - missing a through bolt and the brush cover was rusted and floating around.
I think the tar undercoat held it together. Internally it looked clean and unburned.

On the web of all things you can find Genuuuine Lucas through bolts for starters in the range of $35 to $52. (expletive deleted.) You might find a NOS starter in the $500 range, but being shipped from the mid-east.
I did find a shop in California who might have been able to rebuilt the starter, but I had to ship it to them first, and then they'd give me a quote. Being a thrifty New Englander, after days of searching,
I was able to source brand new, never stretched, 1/4-28 x 7 cap screws GR8 and Gr 5 from Ziegler Bolt & Nut House in Canton Ohio. The grade 5 were $1.32 each. $10 minimum order. You're not going to find these babies in a box store.

The remaining through bolt was stretched in the threads, so I replaced it too.

Degreased the starter dog, applied dry graphite and things worked smoothly. Repaired the brush cover which was rusted through and missing it's end clip. Being loose on the starter it might have been shorting out against the positive terminal. After rebolting, bench tested it, voila it spun nicely.

So - for installation, I tied a nylon tiedown strap to the starter and pulled it upwards from ground level, tying it off when positioned about right. Much easier than trying to push it up by hand from underneath. Snugged it in into place, and rebolted it in.

Reattached the ground strap and positive line. Rebolted exhaust pipe. Reconnected batteries, choked the carb, hit the starter and it kicked in like a champ. Not bad for 55 year old vehicle.

Moral: Bolts should never cost more than bourbon.