speedo trouble

[bazz55]

hi there... right... i had found that the speedo drive on the gearbox had partly broke so now i have replaced the part.. taking the car out for a test drive expecting all to be well and nothing i have tested the cable and that seems to be fine...

under examination i have now taken off the speedo cable and spun the wheels in gear and the gear shaft is not rotating...

any reason why this is not turning??

there is a retaining bolt holding the gear shaft that links to the speedo drive, can this be taken out for inspection and can these be replaced if damaged or does the gearbox have to be stripped and examined that way??

help please

thanks bazz

[davidppp]

Hello, Bazz.

Sorry to hear your having multiple problems with this annoying thing!

The way it works is that there is a worm gear on the end of the pinion shaft..now this worm gear is really shonky IMHO..its on a roughly 3 cem long shaft ( bronze), which is retained loosely in a bore in the head of the big stretch bolt which hold the first gear onto the end of the shaft...this retention is by a roll pin pushed through a hole drilled through the head of the stretch bolt..

The worm gear drives a helical gear which is also on a long shaft..about 70cm..this shaft is at right angles to the pinion shaft, and runs in an aluminium plug which is retained in the tail/shift housing by a special set bolt.and has an oil seal..

The end of this shaft is a flat which engages a slot in the speedo drive you have just replaced....


Its hard top see I know..but the next thing to check is that this flat end is undameged and turning with the wheels...remember the differential will simply turn the other wheel unless you chock it...

It certainly sounds like you may have more than one fault..tho' the angle drive you replaced is the most usual fault..

Ask me how I know!

Hopew this makes sense..

Kind regards
David