Re: tacho reads wrong
I would be talking to crane.
your tacho may not be suited to the electronic ignition, and is getting too many pulses, or it just died.
Some of these things run on 8.8v and some on 12v This difference would alone be enough to give the tacho an incorrect reading. Thinking about it, your original ignition was probably 8.8v and the crane is probably 12v.