This is a Volkswagen Vanagon speedometer--late version--all laid apart. The plates in red are two of about 40 special mounts and tools I've built for working on all manner of speedometers. On the left, the plastic main mount, and in its center, the magnetic drive for the speed needle. UNDER the light color, round housing--barely visible--is the worm drive gear for the odometer portion of the unit.
At the top, orange colored, is the printed circuitry for counting off the miles driven so a warning light can come on urging the Vanagon owner to boogie to a V W dealership and spend a lot of money to have a tech push a reset button and turn off the warning light. This B.S. was done in the name of lowered emissions. Dealerships loved it. The owners? Not so much.
To the right, the dual register odometer assembly with its plastic framework. Previous Vanagon speedos had an aluminum framework, so you see the result of company bean counters at work. Look at the BOTTOM, main, register. On the right end you see a white gear. On the left is a much smaller, yellowed gear. Both are plastic and both tend--with age and jillions of miles of use--to get tired and release their press-on fit with the register shaft. Result? No odometer activity, though the speed reading may still work OK.
The FIX is to replace the larger gear, and in this photo the white gear is a new one that I just installed. Additional FIX is to replace the small drive gear on the left, which I have also done in this photo. The "innards" are ready to be carefully lubricated with modern temperature stable, non-hardening lubricants and reassembled.
According to ancient V W Service Bulletins, these late model Vanagon speedos can get noisy. The problem is that the wee bushing holding the speed needle shaft [see the center of the round housing in the main mount, in the photos above] gets worn badly, as the miles build up. This lets the magnetic "can" below the bushing to move around, touching the outer housing, and causing a noise that drives m'lady bananas. I have a FIX for this, too, but this particular speedometer didn't need it.
M'lady can drive this one a couple hundred thousand more miles before it drives her bananas.
City Car Design
5 years ago