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Positive wire for Tach goes...where?

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Tim_80B

Tim_80B

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Hi folks,

A while back I replaced my stock coil and dizzy with a flamethrower and Pertronix dizzy. I did not hook up the tachometer at that time. When I bought the car I recall that the ballast had been bypassed and the white + green wire for the tach was hooked in with the wires to the coil in some bizzare configuration. Where should this wire be placed now? Attached pic shows the wire I am talking about.

A copy of Rick Astley's wiring book is on my Christmas list. /ubbthreads/images/graemlins/wink.gif

Tim
 
Sorry, I don't see any linked picture.

On the RVC tachs there are normally connections for power, earth, lamp, and signal. The white/black wire goes to the coil (-) terminal, the case needs to be well grounded or have a separate ground wire, and obviously the red/white wire for the lamp gets tied into the dash light circuit. Power for Smiths tachs is typically provided with a green wire connected to a switched 12v supply.

The actual connection point for 12v isn't as important as making sure you choose a point that is "off" when the car is turned off. If you have a volt meter it will be an easy task to measure terminals on the fuse box that are only hot when the ignition is turned on. On the other hand, if the dash is still taken apart, you can use an adapter spade lug fitting (1 to 2) to connect the tach's green wire to the "B" terminal on the voltage stabilizer. The "B" terminal on the stabilizer is switched 12v. Remember, "B" terminal, not "I".
 
Apparently my file upload failed.
Oh well, all it showed was the white wire with a green stripe that I gather must now be attached to a switched 12v. connection. I think I can find one of those, given your advice. Thanks much!

Tim
 
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