VDO speedometers are pretty trouble-free, for the most part. However the ODOMETER portion gets tired after while and in order put them into good fettle once again, they have to come apart. This isn't a real easy thing to do, assuming you don't want that nice chrome bezel all boogered up.
This is the anti-booger tool that I designed and built. It clamps the speedo just right, and the handle [with a wedge tool attached to the speedo end] peels the chrome bezel off, slick as a whistle, without damaging the bezel. SLICK!
I have to take off the speedo needle in order to get the number face off, in order to take the speedo apart to get to the odometer bits that go South. The needle is fragile. I'm using a little puller tool that I built--to pull the needle without doing a booger job on it, either. Gentle is the name of the game when working with speedometers!
Voila! the face is off and I have the front half of the speedo in my left hand. I've set aside the rear portion of the unit. I'm pointing to a plastic gear that is in the chain of gears that drives the odometer [and the trip meter as well]. Unfortunately, this easy-to-get-to plastic gear is NOT the one that gives up the ship in these speedometers. ARRRGGGHHH!
See that little brass gear? That little sucker isn't the one that goes tango uniform, either. But it has to be pulled to get to the bad one. The bad one is the GREY pot metal gear just to the right of the numbers register that is on the bottom in this photo, between the last register and the speedo frame. I built the little puller I'm holding. That little sucker pulls that wee brass gear quite nicely. THEN...I can take the numbers drums out, get the bad Grey gear [called an "advancer"], replace it and chuck it all back together. Fun times!
I hate to re-create wheels. So I spent time drawing [in rather a lot of detail] exploded views of all the gubbins in these speedometers. Makes the process of disassembly, cleaning, repair, oiling and reassembly a whole lot easier. So if your odometer refuses to odo, I can make it all better once again, because, see...I speak speedometer...HA!
I've been repairing these VDO speedos for some years now. I don't see them as some sort of mysterious device that can only be repaired after a lot of money has changed hands. Give me a shout--let's talk about what it takes to fix the VDO speedo in your wee Saab.
City Car Design
6 years ago