I had my odometer on my 1993 245 fail this past weekend.
The car was going from 153799 to 153800, and the unit
stopped. This is my third 240 and fortunately my first
odometer failure.

I opened the unit, and looked at the gear using the web
site http://www.davebarton.com/240-odometer-repair.html.
I looked at both the top and bottom gears as seen in
http://www.davebarton.com/240-odo-028.jpg. But both
gears are whole, and surprisingly soft and rubbery. I
could even bend the teeth with a small screwdriver
and they spring back in place.

Since I could not find a cause, I added to the odometer
the estimated 170 miles I drove without its function, and
reinstalled it in the car. While doing this the unit
seemed easy to turn by hand, there was no binding or
sticking.

This morning the unit again failed as the car was going
from 153999 to 154000. This suggests to me it could be
caused by the extra torque required to turn the extra
numbers.

For all those out there that have had gear problems, I
always thought that the gear failed as it became brittle
with age. Could it become too soft to transmit the torque?

This weekend I also took apart my spare speedometer assembly,
previously in my 1991 vehicle, and the gear looked the same,
soft and flexible. I am at a loss to explain the failure.

Thanks for any assistance in troubleshooting this.

Donald E Booth

1993 245, B230F, AW70, 154000 miles
1993 945, B23oT, AW71, 118000 miles

Gone but not forgotten

1991 245, B230F, M47, 118000 miles
1984 245, B32F, M46, 286000 miles