Older Inductive Tach on EI Dizzy setup?

[PtheDude]

Okay so stock setup had the blackwire/whitestripe running from the positve side of the coil, back to tach, the back up to the resistor block and back to ground ( i think ).

 

I've got an EI matchbox dizzy. blackwire/whitestripe goes positive, other side can't go directly to ground, can it? neg pole of the coil?

 

help....

[datzenmike]

On the '79 matchbox, there should be a Blue and a Black/White wire. The Blue goes to the neg side of the coil AND to the tach in the dash. The Black/White goes to the pos side of coil AND to the ON in start and run position, in the ignition switch. (power)

[PtheDude]

Mike, the blackwhite wire runing thru both my tachs has to terminate somewhere. my 75 book states that the blackwhitewire goes to - neg side coil. My BW wire is different than the books, as it wraps around a pole on the tach and then terminates in a female slide terminal.

 

 

 

 

 

 

[PtheDude]

Where you at datsunholic? thoughts?

[PtheDude]

somebody out there has had to have run into this! I connected said wire to the - neg terminal, and voilia! nuthin.

 

I don't want to smoke the tach!

[PtheDude]

to be clear, my blackwhite wire loops around the pole on the tach, like it wants to be hooked up in series, with all the + coil charge running thru it. is that what needs to happen?

[datsunaholic]

You have a '73, dual-point tach. That's why the wires don't match. If you triggered a tach the normal way off a dual-point setup, it would read double when the second set of points engaged.

 

Inductive tachs have to take the place of the coil trigger, sort of like a timing light or an ammeter, so that they're isolated from the second set of points.

 

So, you need to hook up both halves of the feed wire. One end goes to the dist, the other to the neg side of the coil, and the dist-coil wire is removed altogether. But I don't know if it'll work with an EI dist; the signal will be a lot stronger.

 

This is completely based off conjecture (and the fact that I do have a degree in electronics engineering). I'd never seen a Datsun induction tach until I saw yours.

[PtheDude]

My books picture is for a parallel tach. I have a series inductive unit. had to run the neg - from the dizzy, back thru the tach, and up to the coil to complete the leg. so, its working!

 

If anyone runs across one of these bad boys and needs help, hit me up, I can help you out.