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1984 50 hp Johnson not charging

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blazerresto

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OHM tested the 4 wire diode rectifier, tests good, OHM tested the stater that also seemed to test good, can't get any more than battery voltage 12.5, appears to have no output, looking for advise. Read a lot of other threads seems to be a lot of rectifier problems, can they still test good and be bad?
 
blazerresto said:
OHM tested the 4 wire diode rectifier, tests good, OHM tested the stater that also seemed to test good, can't get any more than battery voltage 12.5, appears to have no output, looking for advise. Read a lot of other threads seems to be a lot of rectifier problems, can they still test good and be bad?
Click to expand...
You say ohm tested the rectifier.

There are six diodes in a four wire rectifier Did you individually test all six with the meter polarity one way and then the reversed way. 12 readings altogether. Each diode should have given infinite resistance one way and a very low resistance the other.

It is actually better to use the diode test range of a multimeter than one of the ohms ranges.

Are you checking the voltage between the red DC output wire from the rectifier and ground. Did you rev the engine when testing the volts

ohm testing the stator coils will not tell you if a small number of turns are shorted.

CDI electronics' trouble shooting guide gives more detail.

http://issuu.com/cdielectronics/docs/practical_ouboard_ignition_troubles
 
vics said:
You say ohm tested the rectifier.

There are six diodes in a four wire rectifier Did you individually test all six with the meter polarity one way and then the reversed way. 12 readings altogether. Each diode should have given infinite resistance one way and a very low resistance the other.

It is actually better to use the diode test range of a multimeter than one of the ohms ranges.

Are you checking the voltage between the red DC output wire from the rectifier and ground. Did you rev the engine when testing the volts

ohm testing the stator coils will not tell you if a small number of turns are shorted.

CDI electronics' trouble shooting guide gives more detail.

http://issuu.com/cdielectronics/docs/practical_ouboard_ignition_troubles
Click to expand...

vics, we have 4 wires, one red, one yellow/blue, one yellow/grey, one yellow, through Johnson service manual test we tested all wires/diodes in both directions, infinity one way, had a resistance reading the other on all tests, appears to test good.

Yes we checked the voltage between red and ground, only battery voltage 12.5 at idle and at high rpm.

I will follow up with your CDI suggestion, ill be in touch, thanks
 
put a meter on ac and see if the stator is puttng out at all... you dont need a dva meter to do this..measure between the two wires coming fron the stator...
 
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