syncspeedinc

I went to look at a 928 today and noticed that the milage on the car was over double the advertised milage, the owner claiming that the odometer broke in the last year of owning the car before putting it way for the past 20 years. He claims that in you tap the top of the gauge console while driving that it will jump around. The paperwork for the car seems to support the claimed milage but I have never known the odometers to jump forward like this. Ever heard of this? The car is not currently road worthy so I can't test this theory. What say the experts here? I have done enough reading here to know the basics of the whole odometer plastic gear issue., but no mention of an almost free wheeling milage counter.

Thanks!

davek9

There was someone that said theirs jumped when pressing the "reset" when it broke, not ever heard of one moving by tapping the Pod.
Speedo yes, ODO no.

Hold On

I have a 83 that started to jump forward in 10K increments when the odo went weird. I didn`t notice it until I went to do oil change and noticed it went up 40K. After I put in a new gear and rebuilt odo it went back to normal.

worf928

The odo drive gear breaks a tooth. Tooth falls in between two of the number wheels and gums up their engagement causing them to turn at the same time or at a rate higher than 1:10.

Tapping the dash causes the broken-off tooth to disengage from one of the number wheels. When the faster rotating number wheel comes into contact with the broken-off tooth it moves it around a bit. Eventually this movement cause the tooth to re-engage the adjacent number wheels... goto step one. Lather. Rinse. Repeat.