A10 Speedo cable

[RESTORER]

Hi. My machine is a 1954 G Flash, S/A, STD gearbox with speedo cable exiting the lower front of the outer casing. Oil is seeping out from the end of the swaging, between the swaging and the outer cover. The oil then travels along the bottom of the outer cable and drips off at the lowest point before the cable rises to the speedo. Gearbox oil must be travelling between the driven gear bush and the the driven gear into the cable and I don't see a way to prevent it, maybe it is designed that way to lubricate the mechanism. There is not much oil but all drips are a nuisance. Has anyone else had this problem? Is it just a sign of poor swaging, which a new cable could rectify? Thanks for reading. Restorer. 

[Bess]

Hi,
    It may be worth looking here:

https://www.bsaownersclub.co.uk/bsaoc_forum/index.php?topic=3819.msg18783#msg18783

Best wishes...

[RESTORER]

Thanks Bess, exactly what I was after.  The Draganfly main parts list B3 lists the 65-3396 driven gear bush for all S/A machines, but the thinner parts list, specifically for the 54-57 models, lists the 65-3390.  They are both still available but looking at the pictures, there is quite a difference in design.  Does anyone know whether or not the two parts 65-3390 and 65-3396 are interchangeable on 1954 machines?  I have already purchased a -3390 in 2017 so don't want to buy a -3396 if it won't fit.  The driven gear 67-3175 referred to on Julians Service Sheet No 74 is the only one mentioned in both parts lists, so I can't tell if the part was once supplied with a different part number and will assume for now that I have the correct item fitted.  Whatever I fit, I think I will still go with the heat shrink idea also, if I can get one.  Restorer.

[RESTORER]

And here are the pics!

[JulianS]

The bushes do interchange. The difference being how the case to bush surface is sealed.

The top one is the early version, the outer bush to the cover is sealed by a nut and fibre washer on the extended thread.

The lower one is the later version where the case to bush is sealed by a rubber seal in the narrow machined channel.No nut or fibre washer.

The photo shows a new old stock later version in the original zinc alloy with the driven gear shaft fitted with a flimsy O ring seal to try to keep the oil in.

[RESTORER]

Thanks Julian, useful info as usual. I think the later bush is the way to go now. Restorer

[Bess]

Hi,
    If you use the later here's a link to a triumph seal which could be the same seal used on the BSA:

https://www.ebay.co.uk/itm/TRIUMPH-PRE-UNIT-SPEEDO-DRIVE-SHAFT-SQUARE-SECTION-O-RING-IN-GEARBOX-57-0948-/262310003777

Best wishes...

[RESTORER]

Thanks Bess, another useful piece of info. I assume this is the washer that fits on the outside of the driven gear bush in the newly added undercut. I have asked Draganfly about the later driven gear 67-3175 and they cannot supply one and also do not have a part number or description for the small "flimsy" seal that fits on the outside of it (as shown in Julians last pic). First job is to remove the gearbox outer cover again and see exactly what I have got in there as I think this seal is the real cause of the oil weep.  A trawl on e-bay failed to find a gear or a seal anywhere, so I'll broaden the search. Restorer.

[JulianS]

The O ring is 42 3039, same as used on the original (but not the pattern) A10 tacho drive spindles.

[RESTORER]

Thanks Julian, that gives me somewhere to start. Restorer.