Hi guys,

Sorry for the delayed response but I have change emails addresses and don't seem to get the updates anymore. 

So is the Laygear shaft different too?  Hmm, I thought is was just the drop gear bearing.  Everything else looks the same some I am not worried about the remote and diff connections.

I could weld the gearbox but the crack radiates from the radius of the engine side clamp that holds one side of the diff bearing.  I would have to weld the crack and then machine the radius back to tolerance, which is doable if need be.

I have one other question as I don't really understand how it can be like this; I replaced the gearbox on my new to me 1380 with my old gearbox out of my 998.  I got the right primary gear and the mating of the two went smoot.  I kept all the gears the same as when it was in my 998, including the speedo gears.  So now I drive the car and the speedo is way out (30%) when measured against my gps speed.  I cannot figure out how this could be other then maybe the speedo always was out by this much. anyway, I appreciate your thoughts on the matter.

DAM3167 first motion shaft (18T with the 18mm bearing) are still available here, but getting rarer, they are not as cheap as they were a year or two ago.
22G1371 (18T with small bearing) is still available but only as a kit with a 22G1040

I bought and fitted a couple of DAM3167s this year.

So when you say 'late' 18 tooth 1st motion, do you mean with the larger bearing? I think those are DAM3167 and are extremely hard to find!  I have TWO of the 3-step laygears DAM3168 that are IDENTICAL to the 22G1040, EXCEPT they take the 3 step shaft with the bigger small-end bearing!   I have been unable to find 18 tooth large bearing input gears for a few years.... These are the close ratio sets used in 1275 GTs in the rod-change cases.

Contact me if you want one of the laygears to match up (or have more of those 18T large bearing 1st motion shafts!)... IMO these are better than the 1040s because they let you build a close ratio rod-change that is stronger that the Mk1/Mk2 version. You can use them in a 4-sync remote also, with the modification in my video...

Careful, these are routinely advertised wrong as "A+" close ratio upgrades.... NOT so!  They use the earlier helical-cut gears BEFORE the steeper A+ types with the grooves around the gears.  Also, last I checked, if you DO order one from Mini Spares (as DAM3167) you'll simply get a standard 17 tooth as they have "superceded" the part number to the one still available.  Same thing if you try to order the extra tooth "economy" 1275 A+ primary gear.... you just get a standard 29 tooth, as they "superceded" the part number.  I find this VERY irritating as have some customers who were simply sent the incorrect part with no mention of the change!

I have also used this same method over the years to save worn 14mm nose mainshafts. Both in Mk1 and Mk2 boxes.
In thic case, machine shaft to 10mm dia with a .0004" interference fit.

Inner ring to use is an IR1020/2. Grind the ring flush with shaft end after fitting.

[edit] pic added

Very elegant fix Kevin. When I was the engine shop, I tried to hold onto damaged shafts and such, but the sheer volume at Mini Mania.... soon I had milk crates full.  You guys that have stored this stuff for years will be heros when there's none left, and those sorts of repairs become economical.  Unlike welding up and remachining the small snouts, your fix does not create any weakness.  It becomes as good as most of the A+ mainshafts.

Kevin, I keep everything I remove from old trannys. Not sure how many 14 mm mains I have with but as soon as they show wear they don't go back in. I'm sure I have some 18s as well. I'm still working off a batch of NOS shafts both sizes I bought several years back. I'd need to get a price on having them repaired here. If there is any value to you I can ship them over. Steve (CTR)

Thanks for the info Jemal.

re the old 14mm mainshafts, over here in Oz the 18mm A+ ones are rare. And I have seen some aftermarket shafts which were poorly machined.
I have modified quite a few early shafts to take the 18mm bearing (used here with a late 18T 1st motion shaft and 22g1040 laygear). This gives Cooper S Mk2 ratios, with the bigger bearing. Would also work fine with A+ gears on it.

Mod involves hard turning or cylindrical grinding the shoulder on the old shaft, 2.5mm from the splines, to take an IR1515 or IR1516 Torrington inner ring. You want a .0005" interference fit.

The old 14mm end is cut off flush with the end of the 18mm bearing ring, after fitting. If this ring ever wears, it can be ground through and replaced.

[edit] typo

Here's a video I made for the modification to the A+ 3-step layshaft in any 4-synchro case:

//cooperroadmini.com/2013/11/20/a-gears-in-the-older-4-syncho-mini-cooper-gearbox/

You can do any thing you want to. Pay no attention to the man behind the curtian. Did we consider he may have a pre A+ rod change and the A+ rod? I recently put A+ gears in a 22 G 1128 could do the same with the 22 G 1832, DAM 4818 or DAM 2886. You can open the lay shaft small end bore to accept the three step saft. You would need to use pre A+ drops from your 998 but you will require another pirmary gear. 1275 and 998 primarys are different. If you have a remote the reverse gear comes into play. I can explain that too. Steve (CTR)  

Is it in an area not conducive to welding ?

I would think if you want to use that case/gears it might be best to try to get it welded.

Steve (coopertune) might chime in on the differences.

Unfortunately it's not that easy... The shift linkage style is completely different, as are the diff outputs. If your 'A' is a remote-shift, is it a 3 or 4 synchro?  If a 4-sync with a casting number of 22g1128, you CAN install the straight-cut gearset, but you'll still have the small idler bearing, so you'll need a correct flywheel housing WITH a breather vent for the big engine.

Your BEST fix is to simply acquire another case for your A+ gears... DAM5626 cases are still plentiful and they are the best ones!

I am just wondering what the differences are between the A and A+ gearboxes.  I know the A+ has a bigger bearing for the 1st drop grear but is that all? 

Can I then just change the flywhhel housing plate (that has the larger bearing)and attach to a A gearbox lower case?

Reason is that when I bought my 1380 it had a nice A+ close ratio straight cut transmission with it.  After discovering a crack in the AL casted lower gear box (radiating from the curved face that clamps the differential bearings) I decided I should swap out the transmission with my old A tramission from my 998.  I would like to utilise the close ratio set if possible and just trying to determine the most economic solution.

Thanks in advance for the help.