The previous owner of my sailboat replaced the console Yanmar tach with a fuel gauge. He claims that the tach did not work(due to unknown reasons). The Yanmar replacement tach gauge goes for $180, but replacing it will not guarantee a working tach.
I have come across Tiny-Tach desiel (http://www.tinytach.com/tinytach/diesel.php)
. It works by sensing the high pressure fuel pulses. This tach sound like a great solution for my situation. Does anyone have experience with these tachs? Any recommendations?