Points

[SpitFire6]

Hi,

OK, the academic part.

The condenser must match the coil. Too little capacitance or too much and the spark will suffer & the points will erode with a crater on one of the surfaces and a tit on the other.

Have a close look at your points. Is there a transfer of metal from one side to the other? If so, the capacitance is wrong & you are losing spark power.

I don't remember which way the metal transfer is, as left the notes at work.. You can add capacitance easy by connecting an additional condenser between -VE of the coil and ground; saves trying to fit one under the dizzy cap and close to the points, where ideally it should really be.

Ideally, the condenser should match the coil primary. Like a tuned circuit at resonance. Tiiinngg. 

How to measure one? Capacitance meter or capacitor range on a multi-meter. 

 

Additionally, a large >50Uf Capacitor on the +VE terminal of the coil to ground will increase spark power. If a capacitor is required on the +ve terminal, you will find that you have measurable AC voltage on the +VE terminal WRT to ground.

Cheers,

Iain.

 

Edit: for around 10 quid: EBay # 372129918210

will measure dwell, frequency/RPM and voltage.

& current up to 10 amps AC/DC. I've ordered one to keep in the car. My Fluke is too expensive to leave in the car and this cheap one does it all!

 

 

Edited June 15, 2018 by Spitfire6
Added a meter