TA21 Gear box overhaul

I am endeavoring to improve my understanding of the TA21 gearbox prior to a pull-down and to that end would like to hear from anyone who has taken notes and perhaps images of the various stages. I have the Motor Trader Service Data sheet 202,  the Practical Motorist of June 1959 and of course the Catalogue of Spare Parts. I feel that the first two publications assume a fair amount of prior knowledge of which I am lacking.  Richard Melbourne Posted by RichardWallach 17/01/2016 05:25:27

Angus,  Very helpful. Thank you.  Regards   Richard Melbourne Posted by RichardWallach 18/01/2016 23:14:12

Thanks for the informative post - I am also considering a gearbox overhaul of my TC21. I haven't stripped it down yet so don't know what I'll find but I wonder if anybody knows the specification of the bearings and where these can be sourced please? Thanks Posted by drdowhitt 21/01/2016 13:27:18

Jon,  The two end shaft bearings are relatively common. Even e-bay has them. They are 6308N being 40 x90 x23 being  a double row single ball bearing. The mainshaft front bearing is I-130520 being a solid roller assembly 3/4"x 1 1/8" x 1"  I have taken the above information from a Jan 1956 SKF Motor Car Bearing Data publication.   I am aware that Red Triangle stocks these parts.  Hope this helps.   Richard Melbourne Posted by RichardWallach 21/01/2016 23:10:27

Many thanks Richard, that's just what I needed to know! Posted by drdowhitt 21/01/2016 23:56:46

Bearings are no problem. You can get them from any bearing supplier. It's the synchro rings that are the challenge.  These are available only from RT as far as I know, but they are blanks and will require machining to mate with the cones. The rings come with machining instructions, but the instructions are incomplete, so your machinist will need to accurately measure the inside of the cones and machine the spiral of the new ring to match.  Not easy. Posted by Angus D'Arcy-Drake 25/01/2016 12:39:59