Odometer rebuild tips?

[Chuck.H]

I'll give you a tip for when you get it back together - NEVER press the reset button, ever!

This is the only way I've found to guarantee they don't break again. After having two broken gears in 100k miles, both while fully stopped, both while gingerly pressing the reset, I stopped doing that and my last fix (both times professionally fixed BTW) has lasted over 250k miles.

HTH,
Chuck.H
'89 TurboLookTarga, 379k miles

[Joe Bob]

When I asked the Speedo shop if that was myth or fact, they stated categorically that it was an urban legend. They break due to age and that their gears have been reformulated and have yet to have a failure. They gave me a lifetime warranty for the gear.

[RedRoseRomer]

Originally Posted by rick-l

There is a reed switch back in the differential that closes to ground when one of the eight magnets are near it. 8 pulses per revolution of the tire.

Thank you, Rick, very helpful.
David

[porwolf]

Originally Posted by Joe Bob

When I asked the Speedo shop if that was myth or fact, they stated categorically that it was an urban legend. They break due to age and that their gears have been reformulated and have yet to have a failure. They gave me a lifetime warranty for the gear.

I heard the same from the North Hollywood Speedometer experts. And they have been doing VDO repair business since the 60's, I think.

[KKothand]

Jgordon, it depends on what you want to do. As someone who did this last Dec, it is relatively straight forward, if you like doing that sort of thing. Otherwise you are better of sending it for professional fix.

I went to OdometeGears.com, they have an excellent writeup with pictures in PDF file, they also sell the gears. The guy is real friendly and I even called and spoke with him so I get the right gear (you have to make sure it has the right teeth configuration for your odometer gauge, as they depend on model and year). This forum also has many individuals who have done this and have shared, do a search. It cost me $30, and my labor. I enjoyed doing it, and learnt a lot about my car (1982 SC) in the process. Right now I am tackling a broken clutch cable, but that is another story....

[porschetub]

You don't need to damage the bezel ring to get it off ,screwdrivers are what screws them up ...seriously ,used a rounded end of a kitchen (table) knife and worked around the edge slowly and over a fair amount of time it popped off and still looking ok.
If you use thin screwdrivers it will look like rats have chewed it,thems the facts ,I have bought junker gauges to learn on,Waynes article got me inspired to DIY and I'am happy so far,have just done this one for a 914 (see pic) and added temp gauge from a junker 911 temp gauge dated to my 911 motor convertion.
North Hollywood is a LONG way away from me after all and I rate other DIY guys that have replied on this thread.

This gauge was purchased with broken glass for peanuts and I have a new class to fit,way cheaper than spending a small fortune for a dual function gauge.