Condensor value...reading the pits?

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pishta

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I thought I read a smart guys description on reading the points to determine what condensor to use, ie. a pit (-) on the stationary side was too low of a condensor value and a mound (+) was too high? if you got the right condensor/coil you had a longer lasting point setup as there would be minimal transfer of material between the points?
 
You are on track but I don't remember which way it "leans." I've had WAY more trouble with leakage on old condensers/ capacitors. On the outboards I don't even use the OEM style caps. I sub plastic "orange drop" caps instead

Also, if a cap is anywhere near the design value, and if they are very old, they are NOT, but if they are "to value," you likely will not drive a set of points long enough to notice the difference


mag5-jpg.jpg
 
The value on most of the mopar are ,25-.285 MF (uf) Jusy FYI
 
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mf and I HATE nf (nanoo nanoo as "Mork" used to say...........)

When I first started reading (old) books on radio/ electronics, it was uuf (micro microfarads) instead if picofarads and they were "condensers." I see no place in the world for "nanofarads." It's confusing and not needed
 
paraphrased from article..."If the condenser is TOO SMALL, it won’t have much effect. You will have a VERY hot spark, but will also have lots of arcing across your points, dramatically shortening their life.." On the flip side..."If your condenser is TOO BIG, it will lower the voltage in both the primary and the secondary by too much. You won’t have any arcing across your points (so they will have a long lifetime)…..but you won’t get enough voltage in your secondary to actually arc across your spark plug, either..." so I guess if your pitting the points quickly, maybe you should go to a larger value condensor. 0.22Uf (corrected) seemed to work universally on these 50's outboards and newer with a mag in this article.
 
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Should be .22uf --- 22 uf is a hell of a big cap compared to what is in a mag or dist.
 
I had a 72 datsun which would require points replacement at 3,000 miles or you would be stalled on the side of the road. Problem was constantly either too much or too little capacitance. It drove me absolutely nuts. The answer may be to simply replace them on a regular basis. By the way, everyone I have ever talked to who owned the Datsun engine I had, had come to the same conclusion.... change them often. I had the advantage of my father being an electronic technician and I was able to measure the condensers so I had an idea of where the sweet spot was but I never was able to find one that would not burn either the stationary or moveable contact...and I forget which was under or over capacitance. That was a lifetime ago.
 
My understanding is the points condenser is in the 0.22-0.25mf range. If there is a build up on the negative point, a slightly lower value of condenser should be used. Slightly larger cond if the build up is on the pos point.
 
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