Engine died during break-in

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67dodgedartconv

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Fired up rebuilt 318 for break in. oil pump primed, carb fuel bowls filled, timing set. Using pertronix
ignition conversion that worked on previous engine. Ballast resistor replaced with wire per instructions. Engine turned over a couple of times and fired right up. Ran to 2000 rpm for cam break in. Had to stop after 10 min for oil leak and had forgotten to tighten distributor clamp down and had to replace alternator because of bad bearing. Had to wait a few days for alternator. Fired it up the next week to finish break in. Started right up but after about 5 min, again at 2000 rpm, the engine started losing rpm, then running rough, and died. Engine would start back up but run extremely rough then die. Now won't start at all. Am getting fuel but apparently no spark. Replaced distributor cap because the graphite button in the top that contacts the rotor was broken. Made no difference. I pulled a spark plug , plugged it into it's wire and cranked engine. No spark. Where do I go from here? Not good with electrical at all. Thanks for any help.
 
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Fired up rebuilt 318 for break in. oil pump primed, carb fuel bowls filled, timing set. Using pertronix
ignition conversion that worked on previous engine. Ballast resistor replaced with wire per instructions. Engine turned over a couple of times and fired right up. Ran to 2000 rpm for cam break in. Had to stop after 10 min for oil leak and had forgotten to tighten distributor clamp down and had to replace alternator because of bad bearing. Had to wait a few days for alternator. Fired it up the next week to finish break in. Started right up but after about 5 min, again at 2000 rpm, the engine started losing rpm, then running rough, and died. Engine would start back up but run extremely rough then die. Now won't start at all. Am getting fuel but apparently no spark. Replaced distributor cap because the graphite button in the top that contacts the rotor was broken. Made no difference. I pulled a spark plug , plugged it into it's wire and cranked engine. No spark. Where do I go from here? Not good with electrical at all. Thanks for any help.
I just had my engine start up and die. After hours of chasing wires and changing out the ecu,ballast resistor and the Coil. I finally figured out I had my rpm tachometer wire grounding out and causing my engine not to fire up. Make sure your getting power to the coil with a multimeter.
 
I just had my engine start up and die. After hours of chasing wires and changing out the ecu,ballast resistor and the Coil. I finally figured out I had my rpm tachometer wire grounding out and causing my engine not to fire up. Make sure your getting power to the coil with a multimeter.
I have a cheap multimeter but don't know how to do this. Do you put neg meter lead on neg coil side and pos to pos side? If not please tell exactly how to do this. Very dumb about electrical. Thanks
 
I have a cheap multimeter but don't know how to do this. Do you put neg meter lead on neg coil side and pos to pos side? If not please tell exactly how to do this. Very dumb about electrical. Thanks

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I have a cheap multimeter but don't know how to do this. Do you put neg meter lead on neg coil side and pos to pos side? If not please tell exactly how to do this. Very dumb about electrical. Thanks
I just learned myself. This diagram is how I figured it out
 
thats to show internal resistance of coil. Pretty good indicator of a coils health. As for the no spark condition, you could set the meter to OHM and touch the leads together. the needle should swing to other side (0) showing a short. Now if you lift and attach the negative coil lead from he pretronix to one side of multimeter and the other to ground and crank the car, you should see the needle swing 4 times per engine revolution. they will swing quickly or may just show a wiggle on the needle. If its a digital , you may see the resistance value go from 0 OHM to some value very fast. If you cant see the digital move, use a wrench on the crank and turn it. The pertronix just triggers the ground connection through a transistor instead of breaker points. It actually goes open to trigger the coil to fire. Also you should set the multimeter to DC volts (50 scale) to measure the voltage to the positive side of the coil.
 
I know of at least two Pertronix that I witnessed go bad. My opinion, they are not heavy-duty enough. Get an aftermarket Mopar ECU and matching distributor, call it a day.
 
thats to show internal resistance of coil. Pretty good indicator of a coils health. As for the no spark condition, you could set the meter to OHM and touch the leads together. the needle should swing to other side (0) showing a short. Now if you lift and attach the negative coil lead from he pretronix to one side of multimeter and the other to ground and crank the car, you should see the needle swing 4 times per engine revolution. they will swing quickly or may just show a wiggle on the needle. If its a digital , you may see the resistance value go from 0 OHM to some value very fast. If you cant see the digital move, use a wrench on the crank and turn it. The pertronix just triggers the ground connection through a transistor instead of breaker points. It actually goes open to trigger the coil to fire. Also you should set the multimeter to DC volts (50 scale) to measure the voltage to the positive side of the coil.
I disconnected the coil wire from the distributor and held to ground while cranking the engine. Got a good spark. Still no spark to plugs. Disconnected neg pertronix lead to coil, put meter on ohms, put other lead to ground. Digital meter was at 1.0 to start. Never changed value while cranking. Is this a good indication my pertronix is bad?
 
I disconnected the coil wire from the distributor and held to ground while cranking the engine. Got a good spark. Still no spark to plugs. Disconnected neg pertronix lead to coil, put meter on ohms, put other lead to ground. Digital meter was at 1.0 to start. Never changed value while cranking. Is this a good indication my pertronix is bad?
Coil wire to distributor,held to ground. This is a poor description.
Coil neg wire and scratched across a ground will make a spark-key on of course.
Coil tower wire near ground and a good spark tells me rotor is bad.
As the cap is new.

I likely would never run pertronics or msd myself, even if they were free. I can troubleshoot point ignition in a couple minutes and electronic ignition in 5.

I dont see any benefit running anything other than oe type electronic ignition on the street.
 
I disconnected the coil wire from the distributor and held to ground while cranking the engine. Got a good spark. Still no spark to plugs. Disconnected neg pertronix lead to coil, put meter on ohms, put other lead to ground. Digital meter was at 1.0 to start. Never changed value while cranking. Is this a good indication my pertronix is bad?
well, the pertronix did fire the coil (did it?) so it did drag off the negative side. If you have no spark to plugs, its losing the bridge between the coil and the plug wires...the rotor. I once had a rotor that was internally grounded sitting on the shaft. Check continuity between the center tower and ground while distributor is in place, then check continuity from tower to carbon button in cap and finally the rotor tip to finger. A grounded spark path will not create a spark. My test would be to watch the coil lead sitting close to ground while cranking. If it sparks, your close.
 
well, the pertronix did fire the coil (did it?) so it did drag off the negative side. If you have no spark to plugs, its losing the bridge between the coil and the plug wires...the rotor. I once had a rotor that was internally grounded sitting on the shaft. Check continuity between the center tower and ground while distributor is in place, then check continuity from tower to carbon button in cap and finally the rotor tip to finger. A grounded spark path will not create a spark. My test would be to watch the coil lead sitting close to ground while cranking. If it sparks, your close.
As tooljunkie said, my description could have been better. When I unplugged the coil tower wire from the center of the distributor cap and held near ground while cranking I got a good spark. Does this mean that the coil and pertronix are good or just the coil? Continuity test from rotor tip to "finger"? What is the finger? Is it the metal strip on top of the rotor that contacts the carbon button? Thanks for your help.
 
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yes. It sounds like the pertronix is firing the coil. The 'finger' (?) is the metal strip that goes from the center of rotor to edge. Its the conduit "roundhouse" for the high voltage spark to each of the 8 terminals. the spark must be able to jump from the tip to the wire towers at the right time too. Very little wiggle room, maybe 20 degrees.
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yes. It sounds like the pertronix is firing the coil. The 'finger' (?) is the metal strip that goes from the center of rotor to edge. Its the conduit "roundhouse" for the high voltage spark to each of the 8 terminals. the spark must be able to jump from the tip to the wire towers at the right time too. Very little wiggle room, maybe 20 degrees.
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Thanks, knew that current passed thru it to the 8 contacts in the cap and on to the wires but had never heard it called that.
 
you may have chewed up the graphite/carbon button again. It can happen if the cap is not seated. you said it just ran rough and died again so it sounds like a tapering off issue, like something wore out in stead of breaking altogether. I'd Check cap and rotor again.
 
Pull distributor and make sure the roll pin is intact. If it broke ,shaft could be moving up and breaking the carbon button.
 
As tooljunkie said, my description could have been better. When I unplugged the coil tower wire from the center of the distributor cap and held near ground while cranking I got a good spark. Does this mean that the coil and pertronix are good or just the coil? Continuity test from rotor tip to "finger"? What is the finger? Is it the metal strip on top of the rotor that contacts the carbon button? Thanks for your help.
well, the pertronix did fire the coil (did it?) so it did drag off the negative side. If you have no spark to plugs, its losing the bridge between the coil and the plug wires...the rotor. I once had a rotor that was internally grounded sitting on the shaft. Check continuity between the center tower and ground while distributor is in place, then check continuity from tower to carbon button in cap and finally the rotor tip to finger. A grounded spark path will not create a spark. My test would be to watch the coil lead sitting close to ground while cranking. If it sparks, your close.
Rotor finger to rotor tip continuity is good. Distributor coil lead tower to carbon button continuity is good. Coil tower lead itself checked and continuity is good. With coil lead pulled from distributor tower and distributor in place, no continuity between distributor tower and ground. What does that tell me?
 
With coil lead pulled from distributor tower and distributor in place, no continuity between distributor tower and ground. What does that tell me?

That tells you nothing because that would be normal.
Pull the cap and turn the engine over to make sure the rotor is turning when cranking.
Make sure the rotor is seated in it's notch in the top of the distributor shaft.
 
That tells you nothing because that would be normal.
Well, that tells you everything if your looking for a fault from a short. Your getting spark at the coil but not at the plugs? Has to be phasing. your not going to see a spark at any plug if the spark is happening between plug contacts. Hard to imagine spark at cap input but nothing at the 8 outputs? They are almost physically bridged by the rotor. Just a small gap.
 
Well, that tells you everything if your looking for a fault from a short. Your getting spark at the coil but not at the plugs? Has to be phasing. your not going to see a spark at any plug if the spark is happening between plug contacts. Hard to imagine spark at cap input but nothing at the 8 outputs? They are almost physically bridged by the rotor. Just a small gap.

Details, details.:D
I don't remember ever seeing or hearing that a rotor or button was grounded out except maybe the spark going down through the rotor to ground, so no continuity between the cap coil terminal and ground would be normal wouldn't it? (that answer is yes):D

The fact that there is spark to the cap but not out of it usually means the rotor is either broken, not seated or not turning. (we could call that phasing if you like):D
Phasing would certainly be off if the rotor isn't seated where it belongs.
Phasing being that far off doesn't just happen for no reason so rotor seated and spinning with the motor seems to be the next verification, right?
 
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Details, details.:D
I don't remember ever seeing or hearing that a rotor or button was grounded out except maybe the spark going down through the rotor to ground, so no continuity between the cap coil terminal and ground would be normal wouldn't it? (that answer is yes):D

The fact that there is spark to the cap but not out of it usually means the rotor is either broken, not seated or not turning. (we could call that phasing if you like):D
Phasing would certainly be off if the rotor isn't seated where it belongs.
Phasing being that far off doesn't just happen for no reason so rotor seated and spinning with the motor seems to be the next verification, right?
I pulled the cap off and turned the engine over and verified that the rotor is turning. Pretty sure it is seated but will check again.
 
I agree, if the rotor wasnt seated, it could have chewed up the carbon button on his last cap too. Id suggest to manually turn the crank with a wrench until you get a spark out of the coil to ground (lay it on a manifold with a screwdriver stuck in it, give it a distance to spark) and then pull the cap and note the rotor location in relation to any plug tower. It should be on it. If its not, the rotor is not seated becasue as Beast said, phasing doesnt just get up and go, its physically tied to the the flat on the rotor shaft. I tried to find a pic of a rotor on a shaft to see where it landed, looks like its right on a reluctor vane.
 
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