225hp Evinrude tacho problem

[tonyaus]

" I have an evinrude 225hp 199

" I have an evinrude 225hp 1991 with 35amp charging system that recently started playing up. It was diagnosed as a stator problem.
We put a new stator in and it goes great again except that the tacho no longer works. While cranking it, the tacho goes up to about 400rpm which sounds right but as soon as the motor fires the tacho goes to zero. It is charging the battery at between 12.6V and 15.2V depending on engine speed. To me it sounds like the tacho circut of the voltage reg. Am I right?? Also if i connect the tacho lead from the wiring harness to the yellow/grey off the stator will the tacho work?? Or does this charging circut put out too much power to run the tacho??
Thanks in advance.
Tony "

 

[dennis]

" tonyasus,

Sounds like a r

" tonyasus,

Sounds like a rectifier problem to me. Joe Reeves
may have a way you can test the pulse output on the rectifier.

dennis "

 

[joereeves]

"Tony.... As per your line of

"Tony.... As per your line of thought, the "Gray" lead coming from the water cooled voltage regulator/rectifier is connected to another "Gray" wire at the terminal block/strip that leads to the sensor portion of the tachometer.

Removing the tachometer gray lead from that terminal and connecting it to the Yellow/Gray wire terminal leading from the stator would be the proper route to take. If the tach works properly with that connection, replace the water cooled regulator/rectifier, then connect the wires in their normal manner.

If however, this makes no improvement, check to see that the 12 volt source is applying power to the purple wire at the tachometer when in the run position. There have been cases whereas the normal 12 volts was being applied in the "Start" position of the ignition switch but not in the "Run" position...... easy enough to check even before you do the above gray wire switching test.

Joe (30+ Years With OMC)"

 

[gaza]

" Hi Joe,
I tried the above o

" Hi Joe,
I tried the above on a 1984 V4 evinrude and the tach worked fine so I left it there worked well till the tach went up in smoke. as the rectifier/regulator works fine except the tach out wire is intermittent. is there a way to by pass rectifier/regulator just for the tach, ie: limit resistor or diode etc. I cannot get a circuit diagam of whats inside the rectifier/regulator. Or do I have to fork out for a new unit.
Thanks in advance
Gaza "