MG Car Repair: speedo pinion on mg midget 1500, mg midget, gearbox

Question
I have just bought an mg midget 1500 the speedo was not working so replaced the cable still not working took out the gearbox pinion which was damaged replaced did about 12 miles speedo stopped took out new speedo pinion this had the same damage any ideas

Answer
Hi keith,
The speedo head or the cable is in a bind and destroying pinions as you put them in. You need to lube and check the cable it's housing to see that it is free and clean with no kinks. Also you need to spin the speedometer with a drill or such and lube the shaft in it so it is free spinning. Then confirm that the pinion is free in it's case and not in a bind when installed in the gearbox. If the housing goes in too far it can put a bind on the pinion and make it hard to turn thus destroying the gear.
Howard