My 99 Merc EFI runs fine at about 5800 rpm's WOT. The last couple trips the tach has been reading high. 7200 at WOT. How can I check if it's the tach or stator or something else?
The motor runs fine and the tach has shown 5800 rpm. The last two trips it has started to read high. Then the last trip it went way high 7200. I'm just wondering if it's the tach or stator?
You should make sure your prop is ok. If it were damaged in a way that affected the pitch, it could allow the motor to over rev. If that happens, you could blow your power head.
Along the line of the previous posting, Check for a spun hub on your prop? That would allow the rpms to shoot up as the engine would be free running w/o any load abd that would definately blow a powerhead.
I fixed my tach. On the back of my tach there is a pot to choose the number of cylinders your motor has. It was set correctly but I squirted a little contact cleaner in it, twisted it back and forth a couple of times and now it's fine. Just a quick fix before shelling out $$$$ for a new tach.
