Re: condensor testing
A LOT of misinformation, though it is all well meaning. A "condenser" in ignition system terms, is two strips of aluminum foil separated by a layer of wax paper. For compactness, the strips are rolled up and put in a metal can, one strip contacting the can, and the other strip contacting the wire. Technically, it is called a "paper" capacitor, paper referring to the insulation. Other types of insulation are used in different, more critical, applications. Paper capacitors are the most unreliable and least accurate of the bunch. It is not an "electrolytic" capacitor, which contains a chemical in the insulation. Typical capacitance in an ignition system is 0.15mfd to 0.4mfd, around 0.2mfd being most popular.
To test one properly, you need a capacitance tester. Since most of us do not have one, an ohmmeter will provide a crude test. An analog meter is by far the best kind to use. Digital---well sort of a guess-test.
To test, remove the condenser and lay it on the table top. Meter range setting is not critical, but something mid-range is ok. Now, hands-off!!! Touching the condenser or test leads will monkey up the test. Before making contact, the meter will read somewhere around infinity (very high resistance). Touch one lead to the case, and the other to the wire, and the meter needle should jump toward 0, and slowly return toward infinity. That jump and return is the condenser charging up to its capacity. In a perfect world, it would go all the way to infinity, but it won't because as I said, paper capacitors are not perfect. The difference between where it goes and infinity represents leakage across the paper barrier. The less leakage (close t oinfinity), the better. If it goes close to 0 and stays there, the two foil strips are shorted together and the condenser is junk. If it does not make the jump and slow return, the condenser is open (very rare). The rate of the slow return is an indication of capacity---fast return, small capacity, slow return, large capacity. You can compare with a known good one for comparison. Leakage robs the system of electrical power.
Once charged up, in a perfect world it would stay charged for awhile. Again, because of leakage it won't stay charged very long. Touch the wire to the case and it will instantly discharge completely, and the test can be repeated.
There ya go folks----capacitors 101.
