Wiring problems Tachometer Mustang -73

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Hi

Sorry Rktman, you have to think of me like a sligthly retarded Swede, I will give you credit for your work in the future =)

I still dont really understand how to connect the wire.

By the way it says on my ignition coil that it is to be used with external resistor saw it on the picture, so of course thats why it is there.

It seems like i dont have a pertronix ignitor. So no im still a bit confused. If i follow your wiring Rktman, i conncet the black cable to the block(ground) and the green cable to - on the ignition coil.

But where am i to attach the RED ? on the resistor input (nr 2 in the pic) or direct on the ignition coil + according to your wiring ?

/Conny
My tach wires like so:

Black to ground - you can ground it to the back of the cluster.

Red to switched power - you should be able to connect it to the jumper you put on the original tach plug.

Green to - side of coil.

 
If you don't have a Pertronix, what kind of ignition do you have? It's important to know what you have to be able to get the wiring correct. Maybe take the cap off the distributor and take a picture of it.
And it says motorcraft 12127 on the backside of it. Do you get something out of the pic?

1617656373563.jpg

 
"You have a stock points ignition. Follow Bob's (Rocketman) instructions on how to connect it. "

You mean Tachman's instructions?    JUST KIDDING, BOB!

Bob is one of the few people I trust completely with wiring instructions and knowhow.  He's the bomb!

 
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Thank you all for all the help. I managed to start my mustang today, it was long since i heard it. And the tach did work.

So i started a new thread about next problem.

But now there is hope for my mustang to get som air this summer.

 
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Sorry got it wrong the tach didnt work think it just was vibrations from the car, had no gas so couldnt test it properly.

So it is connected correct as rcktman said. Back to ground. Green from distside of ignition coil, there i measure only 8 volt and when you press gaspedal it gives 20 volt but still the tach isnt moving. The redwire gives 12 v when turning key.

 
Check that the coil is not wired backwards. I have seen many coils with + (IGN) and - (DIST) posts wired wrong.  The car will run that way, but not that well.

Easy way to make sure:

Take the wires off the coil.
Turn on key switch.
Wire with voltage goes to positive + (IGN) side of coil.
Wire coming from distributor with no voltage goes to negative - (DIST) side of coil.
 

Edit:  20V?  Wow!

 
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