Went on the Hot Rod Power Tour first two days and the speedometer needle was jumpy up to about 35 mph, after which it would settle right in and was what I would call "normal" in terms of needle movement. Up to 35mph, the needle would swing back and forth about +/- 5 mph. New speedo readout. Cable? Thoughts and comments are appreciated.
no problems before this? what type of speedo/trans? if older manual unit the cable may be dry and needs special cable lubricant applied.
Does it make any noises associated with it? I would suggest unhooking and removing the cable from the back of the unit, and pulling the internal cable. Check it for lubrication, a break or an unusual twist. When a cable is correct, it will look like a perfect layering of the cable, with the ends ground into a square, little or no distortion to the cables outer pattern. If the speedo cable is dry, it could be hanging up and causing the jump, but you will usually hear it. It could also be a problem within the speedo head, but the cable is the easy part to eliminate.
I had the same thing happen to mine last year . I looked under the car and the cable looked like it had a tight turn in it so I straighted it out a little and seemed to solve the problem. I think it was binding where it hooks to the tranny. Rocky
I don't hear any noise that I would attribute to the cable. The guy that I bought the car from told me that the speedometer had failed and he hadn't gotten a new one. So I bought a new Autometer speedometer and plugged in the cable. It has acted like this since I plugged the cable into it. So I will get after the cable and pull out the drive portion of it for inspection.
My guess would be that it has to do with the cable, if it still does it after you have inspected everything and if it's cheap enough, I personally would just replace the cable and see what happens There's a bit more possible causes, but so far for what I have seen, the cable is usually what causes that sort of problem.
The speedometer in my Safari started doing that last year when the temperature dropped in the fall.It was also making some serious noise.It turned out that the oillite bushing in the head was lacking lubrication.I took the speedo apart and very carefully lubricated the bushing and shaft with sewing machine oil.Just a couple drops and re-assembled the speedo and problem solved.My speedo has been around nearly twice so it was understandable.
Sounds like lack of lubrication to me. Being it is a new speedo I would focus on the cable. Had a similar problem years ago, lubed the cable, problem went away.
I bought some Dorman speedometer lubricant. It should be here tomorrow or the next day. When I get it I will pull the drive cable out and see how it looks and then lube it up with some Dorman. Stay tuned.....and thanks everyone!
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