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Can anyone tell me more about these NOS parts I have in the garage. Any use for a mini?

1st motion shaft with 18 teeth. I have counted them several times and it is still 18 teeth. No part number found.


1/2nd synchro hub. 22G258 / 22G1119. Seems like this is for Morris Minor or MG Midget 1098 & 1275 engine.


Cheers
Derek

Derek,

The input gear with 18 teeth looks like it could be a 22G1371. If it is then this is from the 4-synchro mini gearbox with the slightly closer helical ratios as used in late S, 1300GT, and 1275G. Used with a 22G1040 laygear.

Nice find!

The length of the grooves for the 1st motion drive gear make it look like a 3 synchro rather than 4 synchro. Overall it is too short for a 3 synchro longitudinal engine like MG Midget/Morris Minor engines.
All the references I've seen for minis are that 3 synchro have either 19 or 20 teeth.

Maybe it is a super low gear special for a van?

Where is Simon Wheatcroft when you need him??
Derek

You may want to check the pilot bearing bore dia. in the first motion shaft. I believe they come in 14 and 18 MM. It should be a S / GT ratio part. I picked up a NOS lay gear that matched several years back. If selling maybe we can work something out. Steve (CTR)

That's not a 4 synchro first motion shaft. 4 synchros have the big bearing with a bigger internal diameter than 3 synchro. That should be a 3 synchro gear, but I don't know which laygear it ties with.

As for the first synchro hub, it is a sprite/midget gear (22G1119).

Correct me if I'm wrong, I can't see the roller bearing bore from here. I'm reasonably sure that early four synchro first motion shafts have a 14 mm bore and the later A+ main shafts and first motion shafts went to 18 mm. There is a first motion shaft for the S / GT ratio sets with the 14 and one with the 18 mm bore and they both work with the same lay gear. You just have to match the third motion shaft. I'm currently installing A+ gear sets in 4 synchro remote cases. Can't use the A+ idler gears but get other benefits of a larger lay shaft and third motion shaft. That's using the std ratio A+ gears. I'd need to check which lay shaft matches the S/GT lay gear. Steve (CTR)

Steve, in this case you don't need to know which pilot bearing it takes to know it's a 3 synchro.

3 synchros take the 2A3709 bearing and 4 synchros the ADU7619 bearing. The internal diameter is different.

Compare the following picture to the one shown by the original poster.

There you go learn something every day. I misunderstood and was thinking of the third motion pilot bearing not the ball bearing. I know three synchro take a different ball bearing. Thanks for pointing that out. Steve (CTR)

So we're agreed 3 synchro, but still a mystery of which laygear it matches with.
Someone on this forum must know...

I'd say a 22 G 1100. Steve (CTR)

18t first motion matches 22A288 laygear. Wide ratio, 3.829 first gear. ADO 16 ?.

Sorry I was thinking one tooth up not one down. Computer at home books and parts at work. The 4 synchro has a 18 tooth first motion. I was not aware of a wide ratio three synchro. I have one of the rod change wide ratio and I like it. I'm running a 2.76 with two O/D drop gears for a over all ratio of 2.56. Still spins the wheels with the least throttle and pulls 70 mph at 3000 rpm. I'm getting ready to make a 10 hour trip. Can you guys drive 70 mph for ten hours and still be in England? Steve (CTR)

Found out what it is. 22G716 as there is the same item on Ebay at the moment (with 18 teeth) http://www.ebay.co.uk/itm/Austin-Morris ... TQ:GB:1123.
The owner has checked through old microfiches and found the only reference to ADO16 / BMC1300. To account for larger wheels I suppose.