Gearbox Identification HELP!

[The Hairy Camper]

Anyone have any idea what code this is? Previous owner had no idea as he bought it as spares. No bell housing so i think i pretty much just have this code to go by!

First letter looks like a "D" Second an "L" maybe?? Can't find a box with a DL code though.




Cheers!

[Aidan]

two letters before the rib, probably a ABD from 1984
check the number of teeth on the crown wheel probably 29, maybe 34

[937carrera]

I think you are looking in the wrong place.

The format for a 4 speed is as follows, according to Bentley, page 56:

AA dd [gearbox web]mm Y, where AA is the gearbox code.

Your picture shows the gearbox web, 01 for January and 4 for 1984

The 5 speed is in a different location, same structure, but no web in the middle.

I found using a brass brush in an electric drill worked best to clean the case up, followed by an oily finger to highlight the number.

(Aidan the expert beat me to it )

[The Hairy Camper]

two letters before the rib, probably a ABD from 1984
check the number of teeth on the crown wheel probably 29, maybe 34

Thanks for stopping in Aidan, can you see ABD in the picture? Or have i scrubbed the wrong spot?
I will have a count of the crown wheel teeth tomorrow.

[The Hairy Camper]

I think you are looking in the wrong place.

The format for a 4 speed is as follows, according to Bentley, page 56:

AA dd [gearbox web]mm Y, where AA is the gearbox code.

Your picture shows the gearbox web, 01 for January and 4 for 1984

The 5 speed is in a different location, same structure, but no web in the middle.

Hi carrera, i think you may be right about that being the date. It was where the code was on my old 5 speed, but this may indeed be a 4 speed??
This box seems to say 01 20 94.

[Aidan]

AB(rib)D12 03 4 that's 12 March 1984, the rib was deleted from the area that is stamped after 1984

[The Hairy Camper]

AB(rib)D12 03 4 that's 12 March 1984, the rib was deleted from the area that is stamped after 1984

What would we do without you Aidan

I'll count the crown wheel teeth and update the post tomorrow.

Cheers!

[The Hairy Camper]

34 teeth on the crown wheel. I also noticed the numbers 42 and 236 written on the crown wheel. Are these clues Aidan?





Cheers.

[Aidan]

34 tooth crown wheel 7 tooth pinion so box is 4.86 final drive so is a very early ABD, after 84 they have 29/6 crown and pinion sets 4.83 final drive
crown and pinion matched pair number 236 and pinion height is 63.42mm

[The Hairy Camper]

Merry Christmas Aidan. Thanks for replying today.

Turns out that it's not a suitable box for me then, but at least i know what i've got now

[Aidan]

but worth keeping in case you fit a 1Y or similar in future

[The Hairy Camper]

Thanks Aidan, I'm slowly fixing up a 1Y. I would need different gear linkage I believe, as mine is currently a 5 speed

Is this early ABD box better than a late one? Or not a lot of difference?

[Aidan]

Not a lot of difference, it should have the later 3rd and 4th gears in, but it's possible it has the earlier fine toothed ones like a DU as it's crossover period hence it has the 34/7 crown and pinion same as a DU. It will have the early synchrohub on 3rd 4th if it hasn't been replaced yet which 97/100 times is cracked/will crack. It could be argued the 34/7 crown and pinion set is superior to the 29/6 one as it is Klingenberg rather than Gleeson pattern and the extra teeth means that duty cycle is less for each tooth.

[The Hairy Camper]

Cheers Aidan, I'm not sure why i enjoy absorbing all this information...but i do

Except the part where you said i basically have a 97% chance that the "synchrohub" will be cracked or will crack