07-11-16, 02:03 PM
Hi Timbo,
The tacho shouldn't move when you switch on the ignition. If you do a Search on "crackling noise" the first hit you should get is dated 23 Feb 2016. There's a good explanation and servo test info posted there by Windscreenman.
Hope this helps and allays any fears.
Good luck.
robbo
Whizz kid sitting pretty on his two wheeled stallion.