I have a Suzuki DF140 on a 1960 blazer bay boat. The tach is not reading correct it starts at 1000-2000 rpm idling then shoots all the way around past 7000 when I am no where near that at 3/4 throttle. Just curious if it sounds like I just need a new tach or loose connections could call this. Just thinking it may be a bad tach. Also it is a 2006 model and just curious about the Suzuki gauge if it can be connected to my motor?