Stewart Warner 970 tach and 990B module
 

I have a old 970 Stewart Warner tach and 990B module. Does anyone have a diagram on how to wire it up? I would like to test it. Were these units all for 12 volt systems or will they work with 6 volt? Thanks.

Re: Stewart Warner 970 tach and 990B module
 

I think they are 12 volt only. I've never tried 6 volt. I can post a diagram tomorrow. The wiring is very simple. The monitor is basically a junction block. The only terminals with one wire are the distributor and tach terminals. The distributor terminal goes to the negative side of the coil and the tach terminal is the green wire from the tach. The white wire is the light, black is ground, and red is power.


Jason

Re: Stewart Warner 970 tach and 990B module
 

My junction block has a terminal labeled ign. That is the same as what you are calling the distributor terminal, correct. Thanks for the information.

Re: Stewart Warner 970 tach and 990B module
 

Yes, IGN is the terminal I was thinking of. If you still need the directions I can post them.

Jason