Hi all, how do I tell what gearbox I've got? Final drive ratio, etc. Is there a code on the box anywhere fer e.g.? Or is it turn & count?
Ta.

This any good?
viewtopic.php?f=7&t=2744&p=58770&hilit=input+shaft#p58770

If it's a 'long spline' gearbox, the odds are it will be 2CV ratios, as they're weren't many Dyanes made after the change from short spline to long spline input shafts.

This might also help.



Gearbox input shafts by slcchassis, on Flickr

ken

Thanks Ken that's great!
Being lazy, should have searched the forum, seems everything is here but it's so big that it seems easy to miss stuff...
Right, into the frosty garage to peer @ engraved rings...
BTW on the old, rear turret shift, g/b am I right to presume the thread on the input shaft is for a trafficlutch? And is there a range of final drives on the early boxes too - M4 engined ones, 425cc, vans, etc...?
Can you use a Trafficlutch box without a Trafficlutch?
Thanks again.

Ok, this time I searched but I didn't find the answer.
Going to pinch the gearbox out of the AZU & put it in Gerty for the winter as Gerty's 'box has no synchro which is why I've been taking an interest in it @ this stage of the AZU build.
Here is the box


It is (roughly) 28 : 1 in first gear so a 2CV box.
The input shaft is stable, going round my pile of old boxes the others all wobble around, is it ok to use without the nose bearing?
Thanks

I'm fairly certain that those gearboxes with a 'short' input shaft had a bearing just inside the casing for the crownwheel/differential.
If that's correct, because that bearing is so close to the splined section where the driven plate mounts, there's no need for the centring which would be provided by a pilot bearing in the tail of the crankshaft.

Thanks as ever Ken you star!
Any idea why the variation?

mike

A pilot bearing in the end of the crankshaft was probably more effective.
Cost probably came into the equation as well; quick and easy to drop a needle roller bearing into a drilling/bore in the crankshaft, even cheaper when that needle roller bearing was replaced by an oilite bearing...

Bear in mind that vans are not suited to carry a centrifugal clutch, hence the 8 spline.

Thanks again Ken. Was there a cut off date for these overhung ones? Or was it a 'lets try it this way' for a bit & then revert to crank shaft supported?
I have a gearbox with UJ couplings which has a small tin top (also a UJ box with a big tin top ) which I assume is earlier & this one has a big tin top & 2cv joints, ECAS do a cork gasket for the small tin top but not the large... I'm rambling, sorry.
Viking, it's a ten spline. Not had a happy time with the Trafficlutch so not putting it on either vehicle!

mike

OK I was looking at the picture with the short 8 spline (van box) Also many van boxes have drive shaft with 6 bolts (never found on sedan)