Odometer not working, but speedometer does Options

[Ctrout]

My speedometer works fine but the odometer won't count miles. I thought they worked together. Where should I look first? Trip odometer doesn't work either. I guess this is good though because if ther are no miles being put on, then it will never require a valve adjust or oil change right? (IMG:style_emoticons/default/lol2.gif)

[lapuwali]

Not just 914s, but nearly all VDO speedos of the era, and many Smiths speedos, have the same problem.

The shafts holding the odo number wheels are polished or even chromed, and the drive gears on them are either nylon or pot metal, and only peened onto the shaft. Not glued or positively locked in any way. Over time, the peening can come loose so the drive gears come loose and spin on the shaft instead of turning the shaft.

The PP tech article recommends just crimping the gear center to pinch the gear on the shaft again, but that's a fairly temporary solution. Gluing MAY work, but you really have to disassemble everything and rough up the shaft to give the glue something to stick to. A better and more permanent solution would be a new shaft and gear with a notch and key (or D-shaped, or something), to give a positive lock.

One major contributing factor is people resetting the trip odo while the car is in motion. This is a Bad Thing To Do.

My odo works in my car, but the second it breaks, it's coming out and I'm going all electronic.