I have two (2) 5 piece A+ transmission sets DAM 5626 (case, 2 output covers, speedo & diff housings)  No internals.

Jet Hot washed, walnut blasted...NO damage to either idler gear thrust face.

$500 each  (UK prices from major suppliers $600-700 US)

BOTH SOLD

Careful measurement will show the stub shafts on either side of your idler gear are in fact .875" or 7/8ths of an inch (vs. the .750" or 3/4 inch of the pre A+, remote, and all 3-synchro boxes).    I have successfully bored the 22G1832 Idler bore to fit the bigger bearing, allowing the use of the much stronger A+ drop gears.  It must be perfectly centered, but doable. I've been testing it under my barely streetable 1380 for about 7 years!

Here's my short video clip showing the case modification to run the 3-step layshaft in any of the earlier 4-synchro boxes, remote or rod-change:

https://youtu.be/o9prvygi7bQ

like I said I have never seen one of the casting numbers. A DAM 5626 would do your job and is designed not to crack over the third motion double bearing. 

My contact info is in my profile. Steve (CTR)

PS having some computer issues a text would work. 

Steve, the idler shaft OD is 0.898" as taken on my micrometer today. Best, John

Check your idler gear shaft OD. It looks like I still have a couple of DAM 5626 cases here in VA. Steve (CTR)

I look forward to catching up with you Pete's MrRad! Nice twin cam you have. Best, John

Sorry to have been 'off-line' for much of today, I had to be in Newark to apply for a Grant for Haven of Hope for Kids that I am a Trustee of. Thanks for that information Jamal, it opens up casing options that I had considered unavailable and now think will provide the answer! I really appreciate the input from you, Steve and several others on our excellent Forum. Have a great weekend folks, John

That's a lot of knowledge on their post. Good luck Finding what you need Jackn. That's my twin cam over at petes

The 4818 case DOES have the larger idler gear and is interchangeable with the DAM5626.   The difference is that the 4818 has a 4-bolt 3rd motion bearing retainer!   I likely have a good case here at Mini Mania!   All your 'contents' will fit either case!

 

Steve, the small idle came on 22G1832 as you said, and also on DAM3220 in the mid 70s I believe....

Nothing creative about it. Just a matter of clearing the case for the three step lay shaft. I may have one of those. Got some grass to mow then I'll run back to shop and see. Steve (CTR)

Yes Steve, for the moment I am in a corner and will try the UK next before attempting any creative 'surgery'! Thanks again, I'll let you know how it pans out. Best, John

I believe I listed it and no I don't have one. That's the only one listed I have not seen. It puts you in a corner. That's the A+ gear set with pre A+ drop gears. Chances are you can modify a 22 G 1832 to take A+ gear set and still have small idler to match your clutch housing and gear. Steve (CTR)

Well, I guessed wrong Steve. My casing is in fact a DAM4818 and has an Idler bearing diameter of 1.370"+/-.

As your email didn't include that casing number, I'll assume you don't have one and shall keep searching. Thank you for your willingness to help, I really appreciate it. Sincerely, John

Thanks Steve, I intend to drive over to the shop this morning and will take a note of the casting number. I suspect from your descriptions that I have a DAM 5626, we'll see. I had hoped it was a only a casting seam but the air bubbles were pretty convincing and when the air nozzle was directly applied to one side, the surface water on the other side was clearly being blown out I'm sad to say. I'll get back to you this afternoon. I much appreciate your responses.

John (JackN)

It would be helpful to know the casting number on your broken case. There are A+ and pre A+ rod change trannys and the guts are different as well as drop gears. Casting number on front of box just behind oil filter when assembled. Sorry to say I have lost three DAM 5626 cases to bad third motion double ball bearing failure this year. 22G1832 is pre A+ rod change, DAM4818 has A+ gears and small idler, DAM 2886 has A+ gears and large idler and The DAM 5626 has all improvements A+ gears, large idler, 18mm pilot on main shaft and three bolt third motion bearing retainer. Are you sure it's a crack and not just a casting seam? I Have 6 to assemble four DAM 5626 a 22G1832 and a 22G1128. Steve (CTR)  

Ideally just a good full casing, we will rebuild the innards with what we have Steve. Thanks.

So you are looking for a DAM 5626 rod change gear case or complete tranny? Steve (CTR)

Understood. It's because this engine didn't originally come out of my mid 70's Mini, it was sourced from an earlier Marque (I don't know which though, it has Tappet covers on the side) after my engine was written off.

As you know, the mid 70's mini was equipped with a rod-type configuration hence the need for the later gear change for the older engine. I was hoping that the transmission that I took off would be good after a rebuild, unfortunately not so. John

I'm curious why not using the original remote shift that this engine would have had (?)

Hi Folks; It's nice to be out on the roads again after a pretty tough winter (at least by NJ standards).

Over the winter we have been rebuilding a Cooper S engine. It has gone very well and I've enjoyed assisting and learning from Pete McCarthy (Midnight Auto) in the balancing of pistons/rods/pins etc. Most components are new with the exception of the crankshaft, which was reground by Storm Crankshaft in NY. Anyway, we have turned our attention to the Rod transmission (out of an A-plus with the large center bearing) which was to get a complete rebuild also. After stripping the box, cleaning and washing it, we observed two major cracks on the main bearing casting.

So, I'm calling around to see if anyone has a casing or transmission of this style, they may be willing to part with?

Thanks and happy driving on this St. George's Day! Best,

John