problem with dual point no spark

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DECIPHER

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So i went and installed my dual point today i get zip nada no spark. went and put my old one back and it pops and wont run either now what did i do. damn
 
Did you pull the plug wires out of the cap for any reason?
If so, recheck your firing order (Twice) :D

Disconnect your wire from the points to the coil, make sure at least one set of points is closed and the coil wire should show as a ground.
Connect a test light to the distributor points wire and to the battery positive.
Cranking should make the light flash.

No flash but lit, the points are not closing or conducting when they do.
Not lit, the points are not making contact or conducting when they do.

Keep in mind the distributor has to be grounded to the block for points to work.


After sitting points can get a non conductive film over them.
cleaning them with a little piece of cardboard (like a match book cover) between the contacts with the points off a lobe using their spring as pressure to pinch the carboard usually does it.
 
Bear in mind that distributor drive tangs are not all the same relative to the rotor. So the thing may be out of time.

^^As above the popping may be the dist is 1/2 turn (180 out) off

So far as no spark, hook the thing up on the bench, ohmeter from distributor primary wire to the case. With the cap off slowly rotate and see if resistance goes from a very low value to infinity. If not block one set of points open at a time (light cardboard or even paper) and see if one is not opening. Maybe neither is, LOL. Look for shorts in the terminals of the points, condenser, and jumper wire. If all else fails disconnect the wiring, and check each set of points individually. All they are is a "switch to ground."

it might be the condenser is bad or shorted.
 
yep i have i going to have to start fresh rotate and find tdc1 and check all the wires. i have swaped the wires back and forth between the caps and im sure i have lost #1 tdc.
 
Do you know the "stick your finger in the number one plug" trick?
 
Do you know the "stick your finger in the number one plug" trick?
Ya I'm going to do this morning of course can find my damn plug socket have 2 of the small one and not the other kinda like my 10mm that always disappear haha
 
Well still no spark any ideas what I could of done the dizzy is pretty simple and all new points and cap etc
 
What happened with post no3?

If the points are opening / closing suspect condenser. Make sure you actually have adequate power supply
 
Ya points are set opening and closing eill check again turned over with pressure in cyl 1 with finger to verify tdc turn over diddly squat just for giggles flipped dizzy 180 still nada I have a couple old condensors just after buying new condensor points cap and rotor figured I would be good

image.jpeg
 
OK but are they ELECTRICALLY opening and closing? You checked them "on the car" with a voltmeter, or off the car with an ohmeter? It won't make spark without a good condenser, and of course then there's the coil

What you have pictured there could not POSSIBLY be closing.....I can tell just by looking at that points gap.
 
yeah, thats a pretty fat gap. The lobe tips should just open the points. The less they open (after they close) equates to more dwell. Dual points can get you more dwell because the closing (charge time) time overlaps between the 2 sets of points. remember the coil fires when the gap OPENS.
 
OK but are they ELECTRICALLY opening and closing? You checked them "on the car" with a voltmeter, or off the car with an ohmeter? It won't make spark without a good condenser, and of course then there's the coil

What you have pictured there could not POSSIBLY be closing.....I can tell just by looking at that points gap.
Agreed! The rubbing block on the points is just about to the high point on the cam. The gap looks like about .030. It should be around .015. There is a procedure for adjusting each set of points separately with a dwell meter but the .015 gap each works pretty good.
 
yeah, thats a pretty fat gap. The lobe tips should just open the points. The less they open (after they close) equates to more dwell. Dual points can get you more dwell because the closing (charge time) time overlaps between the 2 sets of points. remember the coil fires when the gap OPENS.
Yes, one set makes contact and the other set breaks contact.
 
Looks like the Falaise gap of WWII fame. You can march 30000 men between it.
For the love of God set the gap to .017".
yep i have i going to have to start fresh rotate and find tdc1 and check all the wires. i have swaped the wires back and forth between the caps and im sure i have lost #1 tdc.
Yah think?
 
That gap looks like 80 to me. :D
One other thing I can think of is that a LOT of people make the mistake of putting the wire on the points in such a way that the connections isn't insulated from the points body/ground.
The wire connector has to be away from contact with the base of the points and only in electrical contact with the arm that moves.

Hope I splianed that ok. LOL
 
That photo was while I was rebuilding it was set and checked when I installed it
 
You didn't set the gap as the DWELL setting did you? Below is right out of the '70 Factory manual, for 440-6, dual point. Point gap .014--.019", this is to start with, and should be set "with dwell"

In fact after I changed about 5 sets of points "back then," I hardly EVER used a feeler. I just jacked them open "by eye" and then set them "on the starter" with a dwell meter. Sometimes, you have to jack them because dwell sometimes changes between "on the starter" and "running"

dualpoint.jpg
 
Did you double check what I said about the wire that is connected to the points being put together so it is insulated from the base?

Easy test:
Put something like a piece of paper or whatever between the gaps of the points to make sure they are not touching. (closing)
Do you have continuity between the ends of the wires and the body of the distributor?
If so, the wires are grounded out to case of the distributor because of how the wire is attached to the points.

Not just guessing here, this is important. LOL
 
Here's what this boils down to..........The points are simply a switch to ground. On these type dual point, they overlap. This means only ONE set has to be closed to obtain continuity, but BOTH must be open to open the circuit. So with a test light or ohmeter, "at some point" in the rotation, you should have continuity from the dist. wire to the case, and at some point you should have infinity. The only other thing in there is the condenser. If the condenser is badly enough shorted, you will not have spark, and if it's leaky, none, and if it's open, none. It must be a "good" condenser. In an emergency, you can use the radio cap (hooked to the coil +) for a test substitute. So if you have power and a known good coil, it has to work.

You can bypass the ballast resistor "for testing" by jumpering power right to the coil + Don't leave that sit there for long, as you can burn the points or even ruin the coil
 
when i get off work i will check it with my ohm meter. I have the old condesor
 
So my points weren't closing went through again and it's running. If I move all the plugs one direction what will let me put the vac near the firewall?

image.jpeg
 
Got it laid out right now but the new thermostat I just installed is stuck Haha damn
 
If the timing is where you want it I don't think moving the wires will work.........it will be "up against" the firewall. If you need more advance in the timing, then yes.
 
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