MOT-Forum

For those of you with classic Minis, the day may come when you have to replace your speedometer cable.  Having just gone through this on my '81, I can tell you that it will really leave you scratching your head about how to get it loose from the gearbox if you've got a rod-change gearbox with pot-joint axles.  You can't get to it from the bottom because the pot-joint is in the way and you can't get to it from the top because the lower radiator hose is in the way. 
I found that if you drain the coolant and remove the lower radiator hose you can get to it from the top.  But the cable end is usually stuck to the gearbox with years of built-up grime and you can't unscrew it by hand or get a tool in there.  Never fear! 
If you come back at it from under the car with a long 3/8-inch wrench, you can remove the single bolt that holds the speedo drive cover in place.  Actually, you just loosen it from below and then go back in from above and remove the bolt.  Then you can remove the cable and drive assembly in toto from the top.  Once it's out, you can remove the cable from the drive with a pair of pliers, thoroughly clean the drive, attach the new cable, and then drop the whole thing back in place from the top.  Get the bolt started from the top and, when you can't screw it in any more by hand, go back under the car and tighten it the rest of the way with the wrench.  Just make sure that you have another gasket on hand in case you mess up the old one when you remove the drive.
Attaching the other end to the speedo is a piece o' cake if you've got dual carbs.  If you've got a single carb, you'll probably need to remove the air cleaner to give you better access to the back of the speedo.
Unless you've got a relatively new lower radiator hose, it's probably a good idea to go ahead and replace it while you've got the old one out.