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Tachometer wiring

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positive_earth

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Hey Guys, I'm new here and have a question about Tach wiring. I have consulted many resources and still have not been abble to determine which wires go to which lugs on the back of the tach. Here's some background: 1967 BJ8 3000 Mark III. Car was disassembled and in boxes, so I had no reference during reassembly. The schematic diagrams show 5 main wires : 4 white and 1 green. When viewing the tach from the back there are only 2 terminals, a standard spade type (on the left), and a threaded lug (on the right). I know where the wires come from, and what their purposes are, but I have no idea which terminals get which wires! Seems that all of my resources do not label the above-mentioned terminals...the diagrams I have are poor at best. Can any one post a clear closeup picture, or description? Thanks!
 
Hi PE, The schematic does not show "4 white Wires leading to the Tach. There is a single white wire that comes from the ignition switch, gets formed into a loop and installed in that configuration into the small inductive pick up bracket on the back of the tach. This wire then continues on to the "SW" or "-" terminal of the coil. Consequently, there is only one loose wire to be connected to the Tach's terminal and it is green. All the remaining wires associated with the Tach terminate in Lamp sockets and should not be free.---Fwiw---Keoke
 
Here you go.
5752-PDR_0354.jpg
 

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One thing to note about Greg's picture is the white wire's loop around the tach sensor mount is too loose. When installed this loop should be tight around the sensor's mount.

By the way, on Greg's picture, the white plastic mount is upsidedown and missing the metal "staple" on the outside as well, which it won't work unless you have that on there.
 
Thanks guys for the education! Unfortunately, MY schematic does in fact show 4 white and 1 green going to the tach. It does not, however, explain how they are configured...I'm glad I joined this forum!
 
+_earth,
Me thinks you have a " defective " diagram ! I think there was
a nice color PDF wiring diagram in the tech notes of the forum or perhaps someone posted a link to one. I'll look around to see if I can find it for you. In the mean time,
stop using the diagram that you have for anything ! If it is that wrong for the tach wiring, I wonder what other surprises are in in store for you if you follow the rest of the diagram!
Ed
/bcforum/images/%%GRAEMLIN_URL%%/nonod.gif
 
Thanks Ed,
I forget that thing is in the Knowledge Base. I don’t use that one anymore since I’ve made some changes to my wiring.
/bcforum/images/%%GRAEMLIN_URL%%/blush.gif
 
Hi....If you no longer have the Staple, what does it look like and what would be a substitute? My tach worked before I replaced the dash but now it's dead. Thanks, Joe
 
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