PORSCHE 928/944/951/968 ODOMETER GEAR
This guy has the odometer gear for sale. These are the gears that break when
you reset while moving and cause your odometer to stop recording mileage. If
your odometer is not working, this is probably why. They fit any late, 85.5-,
944/951/968. They also fit the 928 up to 1989. They are $40.00 each including
shipping within the continental US. Shipping outside the US may be more.
$40.00
Payment by money order or Paypal ( www.paypal.com ). If you have any other Porsche parts needs, feel free to email him. He will do his best to make you a great deal.
Original taken from: http://members.rennlist.com/slevy6/gear.htm
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How do I know how many teeth the gear should have?
If the gear is crumbled and you can’t count the gears anymore, you need to
count the partner gear.
So the total number of teeth of the partner gear added with your crumbled gear
should always be 70.
So if your partner gear has 49 teeth, you need a new gear with 21 teeth.
Last month I also replaced my gear : it was 20x21 for my euro 928S of 1980
My friend had a euro 928S of 1984 and his gear was 20x32
Gerrit Dreesen
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Description:
If the odometer/daily odometer on your vehicle has failed, then this gear is
almost always the cause. The original beige-brown gears crumble over the years
due to a material defect and must be replaced.
Dimensions:
Total diameter = 17.60mm (20 teeth)
Diameter of smaller gear = 12.05mm (29 teeth)
Measured from tooth tip to tooth tip
Variants:
Most 928 with KM/h speedometer have the 20x32 installed. Simply search for
"20x32" in the store. Models with mileage speedometer always have the 20x21
fitted.
We can say with great certainty, but not with 100% certainty, which model has
which gear size installed. Too many influencing factors (engine
type/transmission type/transmission/differential type/year/model) play a role
here.
However, the following data will reliably help you determine the correct gear:
20x21 (17.60mm/9.00mm) Number of teeth opposite partner gear: 49 teeth 911/928
mph/944
20x22 (17.60mm/9.40mm) Number of teeth opposite mating gear: 48 teeth 911/944
mph
20x23 (17.60mm/9.65mm) Number of teeth opposite mating gear: 47 teeth
944(S2)/911(G)
20x29 (17,60mm/12,05mm) Number of teeth opposite partner gear: 41 teeth some 928
km/h
20x30 (17,60mm/12,55mm) Number of teeth opposite partner gear: 40 teeth 911/944
20x32 (17,60mm/13,40mm) Number of teeth opposite partner gear: 38 teeth 928 km/h
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Example: 944 Odometer Gear Replacement
1) Remove 9 screws holding front/back together.
2) Remove 4 screws holding speedometer in housing.
3) Gently pull off speedometer needle and remove 2 screws holding face on.
4) Remove 4 screws hold halves of speedometer together.
5) Picture of two halves separated. Brown gear on the right is the one we want to get out
6) Using a paperclip, push out pin holding in gear.
7) Remove e-clips holding next 2 gears in place.
8) Be sure to clean the broken gear debris out of the good gears or they may bind.
9) Silver race goes on shaft BEFORE new gear.
10) Reuse e-clips to hold gears in place.
11) New gear in place and speedometer re-assembled.
12) Be sure to get trip reset plunger into solenoid.
13) Install the rest of the screws and job is complete.