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Have spark on only one set of points in my dualpoint distributor

Dean Prevolos

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I have no spark on one set of points in my dual point distributor, original to the 1967 Charger Hemi. I am checking all of my wiring as I have installed all new wire harness.
I brought the #1 to TDC, installed the distributor and was setting the points before I did the dwell. I have spark on the primary points but not on the secondary with the condenser. So I changed out the new condenser with my old one to see if it made a difference. Nothing changed. What would cause the one set of points to not have a spark when cranking the engine? Thanks in advance.
 
I think a correctly working dual point set will have the a spark only on the trailing set of points. both sets are tied to the condensor through the points lead. the leading set of points doesn’t break the load of the coil that’s on the trailing set.
 
I think a correctly working dual point set will have the a spark only on the trailing set of points. both sets are tied to the condensor through the points lead. the leading set of points doesn’t break the load of the coil that’s on the trailing set.
Yup... BeeKeeper nailed it..
 
I think a correctly working dual point set will have the a spark only on the trailing set of points. both sets are tied to the condensor through the points lead. the leading set of points doesn’t break the load of the coil that’s on the trailing set.
YES.....but if the visible spark is "bright" it may be indicative that the condenser is failing, as its function is to absorb the voltage of the collapsing primary field of the coil. IMO.....change the condenser. IF you see arcing on the leading or "make" set of points, the ballast resistor may be failing allowing excessive current to the coil OR the coil's primary winding drawing too much current due to internal winding failure. Just my opinion of course.
BOB RENTON
 
Thanks Beekeeper, 1 Wild Rt and RJRENTON, all good observations and comments. I understand what you are all suggesting and will get back to it this weekend. I'm a weekend warrior and have my car offsite , so I can't go to my garage at home and work on it. I'll folow up next weekend.
 
As the cam rotates the first set of contacts open, but the other is still closed so you're not breaking current. When the second set of points open they spark as they break contact and fire coil. Both open now. Then the first set closes first to resume charging coil despite the second set still open. This is how a dual point can provide a greater dwell (charge time of coil) than the single point. One set does firing of the coil and the other set does the closing to resume charging coil.
 
One set makes contact to charge the coil. The second set breaks contact causing the coil to discharge to the cap and spark plug. The overlap in degrees between the two sets allows the coil to be charged longer for a more intense spark.
 
As the cam rotates the first set of contacts open, but the other is still closed so you're not breaking current. When the second set of points open they spark as they break contact and fire coil. Both open now. Then the first set closes first to resume charging coil despite the second set still open. This is how a dual point can provide a greater dwell (charge time of coil) than the single point. One set does firing of the coil and the other set does the closing to resume charging coil.
Thank you, appreciate your response to my question.
 
One set makes contact to charge the coil. The second set breaks contact causing the coil to discharge to the cap and spark plug. The overlap in degrees between the two sets allows the coil to be charged longer for a more intense spark.
Thanks Toolmanmike
 
It turned out that the one set of points was hitting the top of the hold down screw when it opened. So I grounded down the top of the screw and put it back, now I have the clearance and it does not ground out.
 
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