I have a Mercury 150 EFI 2 stroke. The tach stopped working prompting me to look at the rectifiers. They were both shot. I replaced both rectifiers and ran the motor at an idle. My multimeter confirmed the voltage at the battery increased when the motor was running and the tach was working. I increased the RPMs and when it got around 1500 RPMs the tach stopped working, I shut the motor off and confirmed the two new rectifiers were burnt out. The 15 amp fuse on the red output from the stator was not blown. The motor runs well except the tach and the charging so one part of the stator must be good. The cost of a new stator is not cheep, so I was hopping to get another opinion before replacing the stator and two new rectifiers. Is there a voltage regulator built into the stator before the rectifiers and if so could that be the culprit? Something I am missing? And info is appreciated.