Gearbox and Speedo problems

[keithSB]

Hi

I have recently had my speedo overhauled.

Once fitted everything eas fine for the first 40-50 miles on a long run then the speedo failed again.

As it was under warranty I took it back and when opened we found there was agreat deal of oil present which just stopped the magnets doing their thing.

The diagnosis I was given was that there must be an oil seal gone in the gearbox which is letting too much oil up the cable to the speedo.

This would certainly fit with it taking 40-50 miles before the failure, and there was certainly a lot of oil present.

On looking in the bible it appears that the speedometer pinion comes complete with an oil seal assembly.

My question is do I just replace this Speedometer pinion and oil seal, which I believe I can do with the gearbox in place, or do I have a bigger job on my hands which will involve taking the gearbox out and stripping it.

Or alternatively does anyone have a different opinion of what the cause might be.

I have considered that the cable might have been too generously oiled when it was replaced lately, but I really dont want to just clean the cable and take a chance on the speedo failing again, as I wouldn't feel happy asking for it to be cleaned a second time under the repair warranty.

All input welcome

Cheers

Keith

[bmcecosse]

The problem will only be at the gearbox connection - unless you have grossly overfilled the box of course! But indeed - you should strip and clean the cable before refitting.

[izzi]

Hi,
I am sure you can change the speedo pinion and oil seal with the gear box in place.

When you disconnect the cable from the gear box, It may reveal the leak,if not could be oil leak from oil pressure pipe above speedo unit.

Roy.