Needs some wiring help

[Old Snarlie]

I am wiring up my 72 EXT 340.. all I will have is the tether and the tach.. no lights.. anyone know what wires I need to take off the engine wires for this... also  do I ground the engine to frame or is there a wire for this also.. thanks

[Vintagesleds.com]

[duane]

Yellow can be for tach or lights, brown is ground, I also ran a additional ground from engine to frame.

[Old Snarlie]

Thanks Duane.. I am looking over a 73 tigre diagram now.. problem I am having is I have a black wire from the harness attached to the engine harness plug.. when I use jumper cables to test for spark and placing a tether in the circuit it kills the spark when roped... when I fire it up it stays running... that black wire comes from the CDI if I remember right and a white one also...  anyway gotta let the garage fog out while I try to figure this out.. funny never had a sled that I couldn't get to stop.. had lots I couldn't get to start.. go figure..

[Old Snarlie]

Got it.. I had to run the wire back from the tether to the brown off the engine.. so black wire from harness to black on tether,, then red on tether back to brown on harness.. just have to ground the engine externally and good for now...

[duane]

CDI?

[Old Snarlie]

Yes it is a CDI.. When I use the yellow for the tach ,,,if I am reading the diagram right I go to the tach with one yellow and back to the other yellow... and should I put  a voltage regulator on it...  I don't want to fry the tach.. I will use jumper cables till I get it working so I can get the power off quick if it is wrong....and hard wire it after if it is right... thnks