If you're having tachometer issues perhaps this will help. Last fall I bought a 2004 Tracker 175. It had a 2021 Mercury 40hp, 4 cylinder outboard. The tach would instantly max out when I engaged the throttle. The manual said the max rpm is around 5,500. There are several settings on the back of the tach so I moved it to the one suggested by the help desk at Mercury, 2P4C. The P stands for Pulse and C for cylinder. See pic for the various settings on the back of my tach. The 2P4C setting didn't do anything. I was starting to think that the 20 year old tach wasn't compatible with newer outboards. Today I had the boat on the Detroit River and had left the instrument panel open so I could access the tach. My plan was to move from one setting to the next and see if one seemed to work. It took several tries but the 6P setting seems to work perfectly. The needle moves in proportion to the throttle and it maxes out right around 5500 rpm. So, if you're having issues perhaps my experience will help. B
Fi
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