Easiest way to disconnect Tach on XKE Series III

[sammyb]

My inlaw's Series III E-type has a tach that bounces wildly. We're all sick of watching it bounce around, so until it's fixed, I think I'll just disconnect it for them.
(It's an automatic, so it's a non-issue.)

What's the easiest way to disconnect the tach? I gave a quick look once and it seemed that there's not much room to get a hand behind the dash...can it be disconnected from the engine bay or some simple way?

Thanks,
Sam

 

[Keoke]

Sam,I am not an E type garu,but if you look on the back of the engine ,driven by a camshaft, you will find a little generator that drives the tach .Two wire terminals protrude from it. Just disconnect one of the wires and then see if the tach isnt silenced.FWIW---Keoke

 

[KerryStagmer]

im not up on the series 3 cars, but the camshaft tach drive was eliminated by series 2 (1968)so i'd be suprised if the v-12 used it.

 

[John S Farrington]

The 12 cylinder E Type tach is driven by a wire from the coil/distributor signal. Since there are original ignition arrangements as well as after market solid state conversions, I hesitate to tell you what to look for for this signal disconnect. The tachometer drive wire from the ignition system is either a white with black stripe or a white with blue stripe color code. If you take the under dash scuttle loose and look to the rear of the instrument you will see the signal wire and should be easy to unhook. The wiring for the panel light is white/red. There is a 12 volt wire and the signal wire. The 12 volt switch wire will also disable the tach. Hope this helps.

 

[sammyb]

Thanks John!

Will do it next time he brings the car down.