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-   -   Bouncing tach needle (https://www.yenko.net/forum/showthread.php?t=99173)

firstgenaddict 05-31-2008 07:13 PM

Bouncing tach needle
 
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 06-01-2008 12:43 AM

Re: Bouncing tach needle
 
I had a similar problem and it was a bad ground ...

njsteve 06-01-2008 02:51 AM

Re: Bouncing tach needle
 
I had a similar problem years ago and it was a bad connecting rod.

Good news: the tach needle stopped bouncing. https://www.yenko.net/ubbthreads/imag...mlins/grin.gif

Bad news: the rod went through the block. https://www.yenko.net/ubbthreads/imag...lins/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 06-01-2008 04:12 AM

Re: Bouncing tach needle
 
[ QUOTE ]
I had a similar problem years ago and it was a bad connecting rod.

Good news: the tach needle stopped bouncing. https://www.yenko.net/ubbthreads/imag...mlins/grin.gif

Bad news: the rod went through the block. https://www.yenko.net/ubbthreads/imag...lins/frown.gif



Remind me to never let you drive one of my cars! https://www.yenko.net/ubbthreads/imag...s/rolleyes.gif https://www.yenko.net/ubbthreads/imag...mlins/haha.gif https://www.yenko.net/ubbthreads/imag...mlins/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 https://www.yenko.net/ubbthreads/imag...iggthumpup.gif

firstgenaddict 06-01-2008 08:12 PM

Re: Bouncing tach needle
 
Thanks... will try it.


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