New Tach does not work. Any suggestions.

[BamaBear_1961]

Ok, 94 Evinrude 48 SPL. 4 Wire rectifier (3 yellow, one red) 79 Vintage OMC tach new in box with 5 pulses/revs printed on face. Grey wire connected to yellow/grey and black grounded to engine block. Purple wire connected to switched power at ignition. Tach jumps when switch is turned on but does not work when engine is started. Ground has been checked power has been verified at switch after engine is running. I have been working on this thing all afternoon with no luck. Any suggestions?

 

[BamaBear_1961]

Re: New Tach does not work. Any suggestions.

Bump

 

[BamaBear_1961]

Re: New Tach does not work. Any suggestions.

 

[rodbolt]

Re: New Tach does not work. Any suggestions.

hello<br /> with the engine running and water supplied to it check for AC voltage on the gray wire at the tach. it should increase and decrease with RPM. if it does not go to the yellow gray terminal on the terminal strip and retest. if it still does not, test the stator and rectifier.