Tach trouble shooting

rioraton

Cadet
Joined
Sep 11, 2011
Messages
8
I have a 92 Nissan 90 NS 90A 3B7-1 Outboard My tach stopped working or should I say worked intermittently. Replaced with New/used one. Still does not work. So, I think I have a wire issue. I do not know how to go about trouble shooting the issue. I have the following wires: Blue & Black Wires, Yellow & White wires, and Green and Red wires coming out of tach. What are each wire for, where do they go and How do I test them with multimeter. ANY info would be helpfullView attachment 359496View attachment 359497View attachment 359498
 

rioraton

Cadet
Joined
Sep 11, 2011
Messages
8
Check your regulator / rectifier.
No regulator? If Rectifier is the issue would I have charging issues... which at present i do not have? I do not know if the tac signal wire is white or yellow the rest of the wires I know what they are for I ASSUMED the yellow is signal ground cuz on the wire diagram I was sent it ties in to a black ground wire BUT I do not know for sure.
 

legalfee

Petty Officer 1st Class
Joined
May 10, 2018
Messages
304
No regulator? If Rectifier is the issue would I have charging issues... which at present i do not have? I do not know if the tac signal wire is white or yellow the rest of the wires I know what they are for I ASSUMED the yellow is signal ground cuz on the wire diagram I was sent it ties in to a black ground wire BUT I do not know for sure.
Voltage comes from the stator. Boat will run without RR but will eventually burn something out. Only way to know for sure is to measure the output with a DVA meter or oscilloscope.
 

rioraton

Cadet
Joined
Sep 11, 2011
Messages
8
Voltage comes from the stator. Boat will run without RR but will eventually burn something out. Only way to know for sure is to measure the output with a DVA meter or oscilloscope.
Thanks! Ya, I have seen them do this on youtube. It could be the rectifier I did hook the battery up wrong several years ago and it blew a fuse and may have blown a diode too in the rectifier. I will ck it out Thanks
 

jhande

Petty Officer 1st Class
Joined
Jun 26, 2010
Messages
372
Silly question...
I didn't see a pulse selector, I though boat tachs had them?
 
Top