This is a repost because of a mis-spellings is the previous subject line.
I have a 1949 3100 that I have been working on, and haven't driven in awhile. The speedometer does not seem to be reading right. It reads 8-9 mph low at slower speeds (10-30 mph), but by the time it gets around 45-50 mph it is pretty much on. I checked the speeds against a GPS, plus I can just tell at slower speeds its not reading right. Any ideas? Do the magnets in these go bad?