Bouncing tach needle

[firstgenaddict]

The tach needle on the Z starts to go crazy at 6000 RPM or so... and bounces around from pegged to 3500 then when you get out of it the needle falls back to normal. Is it the points bouncing and causing the tach problem or is it electrical?

[Xplantdad]

I had a similar problem and it was a bad ground ...

[njsteve]

I had a similar problem years ago and it was a bad connecting rod.

Good news: the tach needle stopped bouncing. http://www.yenko.net/ubbthreads/images/graemlins/grin.gif

Bad news: the rod went through the block. http://www.yenko.net/ubbthreads/images/graemlins/frown.gif


I would say bad ground for the dash/gauge or check the terminal end on the coil to see if it the copper wires are all broken except of a couple strands left. You may want to cut and recrimp the terminal end that mounts on the coil.

[Verne_Frantz]

[ QUOTE ]
I had a similar problem years ago and it was a bad connecting rod.

Good news: the tach needle stopped bouncing. http://www.yenko.net/ubbthreads/images/graemlins/grin.gif

Bad news: the rod went through the block. http://www.yenko.net/ubbthreads/images/graemlins/frown.gif



Remind me to never let you drive one of my cars! http://www.yenko.net/ubbthreads/images/graemlins/rolleyes.gif http://www.yenko.net/ubbthreads/images/graemlins/haha.gif http://www.yenko.net/ubbthreads/images/graemlins/haha.gif

I agree with Steve that it's a connection that's causing the problem. Interrmittent ground or the trigger signal from the coil. As long as the engine runs smooth and strong, it isn't anything in the ignition system. If you re-establish the continuity of all the tach connections and you still have the problem, the tach is broken.

Verne http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif

[firstgenaddict]

Thanks... will try it.