This critter is a speedometer from a 1990 Porsche 964. I call these "hybrid" speedos because while they are ELECTRIC [not cable driven], they still retain the mechanical
The usual problem with these speedos is the break-up of a couple of wee little odometer drive gears that were shit quality to begin with. Of course, you have to
take these things all apart to get to those little gears. On the left, above, is the
speedometer assembly, with its printed circuit board. In the middle, a plastic gasket, and on the right, the outer, steel, "can" or housing. The outer rings and the [plastic]
glass have already been removed. [Uhhh...PLASTIC glass? In a Porsche? Oh my...]
Here the printed circuit board has been separated from the main frame of the speedometer. We still are no where near the busted-up wee gears, but we're
gaining on it...
Believe it or not, this mish-mash is a little pancake motor that drives just the speed needle. It is fed by a little sensor somewhere in the bowels of the car, driven off the
final drive of the transmission. And...of course, there is another little motor that drives the odometer gears. And, assuming you can find THAT motor, you'll find the little busted drive gears jammed in behind it. Keep looking...
See, when the crappy little gears shredded, they sent little gear bits all through the
rest of the speedo. You have to take the bloody speedo all apart--usually--in order
to use dentist's torture tools to dig out all the little gear parts. If you don't, those
broken up parts will sure as hell screw up the new gears you install. Fun stuff....
Here is the reconditioned, CLEANED-UP, speedometer, WITH new wee gears. The
new gears are made of a different, high quality material that will probably outlast
the rest of the speedo. They will certainly outlast the [plastic] "glass"........HA!
City Car Design
6 years ago