Engine instruments
Having looked into the problem of replacing the "idiot lights" on my 2QM15, here is what I found or did.I installed an alternator driven Tachometer. Teleflex makes one for diesels. I had Yanmar add an additional wire to the 35 Amp alternator for an output to the Tachometer. With an independent calibration it seems to work OK.You can buy a temp sender for the Yanmar 2QM15 for either the idiot/warning lightor for a temp gauge, but not both. There does not seem to be any other place in the cylinder water jacket to add a second sensor. After thinking it over, the warning light & sound seemed to be the safer option. I added a larger water intake (3/4") and a sea strainer with larger hoses and have not had a problem in three years. As a second option, you can install a water flow sensor on the intake line, as a back-up.