Re: Rising tach?
I had the same problem with a one year old tach on a 50hp Honda. The tach would slowly rise and pin the needle and then it would drift back down. As already suggested, try removing all the wires on the back of the tach, cleaning and then reattaching. Also, if that does not work, you can turn back and forth the pole selector on the back of the tach (dial that has an arrows with letters like 5P, 2C, etc. Note where the selector was pointing to begin with and put it back to that spot. If this does not work, you likely have a bad tach.
