1986 Alfa Romeo Spyder. WHen stopped, speedometer shows about 12 mph. At highway speed, it shows about 20 mph. Odomater seems fine.
Phylspilot, my 86 Spider never displayed less than 10 mph. If you look closely, you should see a tiny pin that the needle touches at about 10 mph. That prevents it from ever falling to zero. The needle will not move up until the speed exceeds 10. From my experience, that is normal. In your case, not displaying >20 is NOT normal.
The problem could be a few different things. Since the odometer appears to be working ok (I assume you checked that it racks up the miles at a rate commensurate with your approx speed), the speed needle may be sticking. I had the opposite problem with mine - speed needle okay, and odometer messed up.
I recommend pulling the speedometer housing out of the dash and checking to see if anything is causing the needle to bind. If it isn't, then check the fine spring where the needle is attached to ensure the spring is okay. You should be able to move the needle with your finger smoothly and have it return gently to the start position (in your case 12 mph).
This is a tricky operation. If you remove the needle from the stem, carefully place it back on the stem. Do this without moving the stem. Just reinsert the speed needle on the stem exactly at the small pin that holds the pin at about 10 mph.
Check the entire speedometer housing for cracks. Any crack could be enough to prevent proper operation. (That was the source of my odometer issue.)
Have fun putting it all back together.
Mar 20, 2013 |
1986 Alfa Romeo Spider