Hello fellas,<br />I have a 25' tracker pontoon. I have noticed that my tach is not working properly on my boat. I noticed that when I am in rough water my tach jumps all over the place sometimes. So then I also figured out that if you tapped the front of the tach (plastic bubble cover)the tach will jump from wherever it is up about 2000 RPM.Basically I can make the tach needle move up or down by tapping it. A boat mech said that there were a couple of screws on the back of the tach that needed to be tightened. Anybody have any ideas why it would do this?Loose connection? Faulty tach? <br />Any ideas? On how to fix?<br />Jeremy