Re: Guess it might not be the points.... Suggestions!?

Posted by BH On 2012/8/20 20:48:24

While most DIYers don't have a capacitance meter, there's a simple test you can perform with an analog multimeter (VOM, with a needle-type gauge) or digital volt meter (DVM, with an LCD readout). I prefer the former. Set the meter to measure resistance in a high range - scale of kilohms (x1000).

If done in-car, you'll need to make sure the breaker points are open. If done off-car, make sure the condenser is not resting on a conductive surface.

First, just to be sure the condenser is completely discharged, momentarily short the pigtail to the case.

Then, hold one probe from the meter to the terminal at the end of the pigtail, and touch the other probe to the case.

If good, the meter will go to to zero, then slowly go to infinity (overload, if digital). If you reverse the leads, the meter will go off scale, momentarily (as the cap dumps its charge), but should then do the same thing. Resistance builds as the capacitor becomes charged (by the battery in the meter)

No change in the meter reading means the condenser is open. This will cause arcing and premature failure of the points.

A steady resistance reading of anything less than infinity (overload) means the condenser is leaking current to ground. (If completely shorted, you'd would have had no spark at all.)