MGB & GT Forum

I am installing a new wire harness to my 67 GT but have some questions on the tach wires. I have the white wires from the coil and ignition switch but not sure how or where the green wire comes from. Should it come from the voltage stabilizer? I have attached a picture of my stabilizer but it does not look like the same one in Rick Ashley’s book. I do not have a solid green coming out of the harness so I am guessing it comes from the stabilizer or comes off another green under the dashboard?
Thanks

I don't recall there being a green wire on a '67 tach. Just the white inductive loop and a white, plus the indicator lamp and the dial light.

There is no green wire on a RVI 2401 tach. The below pertain to the picture:

The backside of a RV1 2401/00B for a September 1966 build MGB. Clockwise from the Yellow spade connector.

On the left, a spade connector yellow with age with a white wire is the main power connector

Background middle, is the light for the tachometer

On the right, is the white wire from the ignition that loops around itself for detecting pulses. This wire continues on to the coil.

Far right is the thump screw and post for holding the tach in place. There are two ground wires on this post. One comes out of the loom, the other is used in daisy chain fashion to ground the lights for the fuel gauge. The second post for holding the tach is behind the yellow spade for power.

Front and center is the light from the alternator or generator that tells if it is not charging. This is best left as an incandescent light. You need some resistance on this wire to excite the generator or alternator to charge. No resistance and you will end up with a dead battery.

Thanks for the info Larry, I think I am all set.

Martin,

Your confusion is understandable. One illustration in the Workshop Manual shows the tach main power wire as green but the wiring diagram shows it as white. The tach will work either way whether the wire is fused or not. Unless a fuse blows.

Silas