Bouncing tacho

[mikey14sr]

Noticed on the trip home tonight that the rev counter needle was dancing all over the place, Often just sitting at zero. All the connections are fine, and the engine was not misfiring, Is the tacho on it's way out?

[Jon_nova1]

try connecting a wire straight from the green wire on the ignition coil to the tacho if its still not working right it could be the tacho in the dash on the way out

[mikey14sr]

Pretty sure I've fixed it now, on the way home tonight when the fan cut in the engine died and the wipers came on!

Had to move the gearbox earth strap on sunday because the threads in the captive nut on the chassis leg were corroded and useless. But there's an earth coming out of the main loom that goes to the same point and I had moved it to the coil mounting bracket.
It seems the electrics didn't like this method, So I've just re-done the earth points and put both the earths together, after cleaning up the contact points with 80-grit paper. Left it idling for half an hour and not once did anything flicker, jump about, suddenly come on or the engine die.

Moral of the story, make sure the earths are perfect!

[Jon_nova1]

erm yer you need the earth strap on the transmission endplate, when we forgot to put it on a relay kept ticking and the wipers came on when you tried to turn it over lol

[mikey14sr]

gearbox end was fine, the bolt to the chassis leg was the problem, had to drill a new hole in the bracket that comes off the leg for the gearbox mount and use a nut and bolt.