914 tachometer acting funny Options

[recko911]

What would be the cause for the tachometer needle to move irregular. It's starts off normal but as I get to the end of the gear it jumps irradically. Then returns to normal. It also feels as if the engine will shut off but it doesn't. Advice would be appreciated.

[realred914]

(IMG:style_emoticons/default/smash.gif) tach get signal from tjhe spark coil. low coil voltage (measure it when running, should be close to battery voltage) can cause proeblms as can bad points. if your still running points I suggest you invest ina Pertronix or simular electric ignition so you r dwell and timing issues will be a thing of the past, you will get better spark timing with electronic ignition plus higher energy sparks as the dwell is maximized for the best spark).

so look for defiencies in the ignition system coil voltage and condition of points (best to replace with Pertronix type device) also check for loose wire and such too. if you have low voltage at the coil you will find better sparks if you can get teh voltage back up to near battery voltage. on one non-914 car i added a relay to give the coil a direct path to the power source rather than the long route (and voltage drop) via the key switch.

have fun (IMG:style_emoticons/default/chowtime.gif) (IMG:style_emoticons/default/driving-girl.gif) (IMG:style_emoticons/default/driving.gif)