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13 years ago in PONTIAC
Answers (2)
13 years ago
Thanks for the advice. Now all I need to do is find someone that can do that for me. I am not willing to attempt it
13 years ago
Hello: When I was in high school and college (late 1970's), I worked at a speedometer shop part time, gardening, toilets, vacuuming, I used to do some shop work, and watch the technicians peek underneath walking-by secretary's skirts while the technicians were under a car ot truck on a creeper. If the head is stuck, and the transmission gear is free, and the cable turns, then the head probably needs reconditioning / rebuilding. DO NOT try to unstick it using WD-40. The shop I worked in used to get a lot of truck speedometers in that had been WD-40'd by well-intentioned drivers and / or mechanics, the WD-40 eventually froze the head as if it had been dipped in lacquer, and then dried. There's not a whole lot to mechanical speedometers; the part which the cable shaft is inserted into has circular magnets which creates close-tolerance magnetic attraction to a very lightweight steel "cup", which the speedometer needle is attached to. The faster the cable spins the shaft that the magnets are attached to, the greater the magnetic attraction to the cup that the needle is attached to, and the higher the needle climbs up the speedometer face, as in Miles Per Hour. There is usually a small thin ring that keeps the shaft with the magnets affixed to the pot metal housing, and once you get the small ring off, usually by putting a punch into the square that the speedometer cable goes into, and hammering it out; the jammed area is usually in the bushing that the shaft goes into, which is pressed into the pot metal speedometer frame. Even if you do it yourself, you won't be able to calibrate it yourself, or know if it is accurate. It takes miniature shop tools, like that of a watchmaker's shop, to do the work. If you farm out the work, consider changing the odometer to something that might be useful to YOU, such as if you put a new engine in it 30,000 miles ago, have the odometer reset to 30,000 miles. You usually have to file the odometer change at your DMV off