`70 Road Runner 440-6bbl keeps konking out!

Go to the post above your last post and do what he said!

This is a tough one . I'd jumper from the batt positive post to the ballast & from the ballast to the coil positive primary terminal & see if it'll act up. This'll take all of the ign1 (run) circuit out of the picture

I just fixed a 6bbl cuda for a guy and it was the aftermarket coil overheating, he bought it at NAPA and it was a Ford coil, did the exact same thing as yours.

One thing nobody remembers, 'cause you're all too young: Breaker point Kettering ignition requires a capacitor (condenser) to keep the points from arcing to hell in 10 miles. It wasn't uncommon for them to short out when hot, then "heal" as they cooled off.

Rick

I had the same thing happen on my red 70' Sixpack Charger. It would just die whenever it wanted to. Most of the time when it was hot (at running temp). It turned out to be the parts store coil over heating. I bought a MSD blaster 2 coil & painted it black. That lasted several years but eventally started doing it again. I am back to another parts store coil & all has been fine for several more years.
I think it has something to do with the location of the coil in the factory bracket that causes it to over heat over time????? My 440 4 BBL cars never do this with the coil mounted further up front hanging off of the front of the intake manifold.

Could be the coil... when it shuts off get out and feel how hot it is. Of course it wouldn't be a bad idea to re-check all your grounds too.

my friend had the exact same thing happening, couldn't figure it out - this was on a freshly restored "everything" 440-6 70 Challenger R/T, and I mean everthing...so it stalls one day while we're out, I'm looking it over, and I notice the coil is kind of "wet" looking - oily residue around the top - it was leaking and heating up and brreaking down I figured, swapped for a new coil and hasn't happened since - not leaking either. I also had the same problem, like someone just reached in my window and shut the ignition off while doing 60 or idling, spoke to a friend at the dealer where I picked up my MP electronic ignition kit and he told me the orange boxes were possible subject to heat soak - to try a chrome box - that was about 8 years ago - never happened again after I swapped to the chrome from orange...my

I've been having the same issue with my 440 six pack. It will stall when it's at operating temp. It will always restart but die out again when it's put back in drive. When it sits and cools of it will be ok. I have an Accel super stock 8140C coil that's about 10 years old. It's getting real hot to the touch. I ohmed out the primary and secondary windings and found them to be within spec.. I removed it yesterday to replace it and found it was leaking oil. I havn't driven it yet but I think this is could be the issue. So you may want to look at your coil as well.

Great, great info you guys! I still have yet to check out the connections at the bulkhead to rule that out... but it sure sounds like a lot of you have experienced difficulties with the coil. That's such an easy check/swap that I might try that first.

Oh, and yes I'm aware of some of the Mopar ignition boxes failing (good suggestion as well!), but this car is equipped with a totally factory correct ignition. (points)

Thanks again guys, and I'll keep you posted!

Dale

still dont forget the points condenser. They have a tendency of get hot and shorting also.

Check ballast resitor and connection and amp meter connection.Steering column to wiring harness connection prone trouble area

4406bbls without the heat crossover blocked will overheat the coil,one of the bracket bolts goes in the head right next to the heat crossover, just my opinion that heat transfers through the bracket to the coil. I relocated a coil and control box to a location inside the nosecone of a Superbird that was a particular pain in the ass for stalling, fixed all the problems. I do not remember having all these problems with oem parts when these cars were new but who knows whats going on.

check the ignition switch.

They may be on to something with the coil overheating. You may also want to check the ballast and ignition switch to see how hot they are. I had a similar thing with a dual point, found out inside the distributor was wore out, shorting out the points and condenser which made the whole ignition system to hot.
Have you checked the rotor and cap? How much wear or movement there is inside the distributor ? May want to check the shaft wear and end play as well, also check for broken springs.
Check the HT circuit, make sure you have a good ground from the battery to the block, battery to the radiator support, block to the firewall, coil/condensor to intake, there should be no paint in the threads or under mounting points. Also check to see if you have spark from the center coil wire to the block, if you have a rapid succesion of blue spark, the coil is ok, could be the cap, rotor, points, next check the LT.
Check the low tension circuit with a voltmeter or test bulb and 2 lengths of wire. With the ignition on and the points open, test from + side of the coil to ground. No voltage indicates a break in voltage from the ignition switch, check all the connections from the ignition switch. If there is voltage it means the coil, condenser or there is a broken wire/connection between the coil and distibutor. Take the condenser wire off the points with the points open, test between the moving points and ground, if there is now voltage then the condenser is bad put in a new condenser. If there is still no reading from the moving point to ground, test the (-) side of the coil to ground, if there is a reading (voltage) on the (-) side of the coil to ground, there is a broken wire between the coil and distibutor which needs replaced. If there is no voltage between (-) coil to ground then the coil has failed. Good luck, just some things to check....

Hey Dale,
One last thing you mention "440-6bbl, 4spd, all done to stock trim and specifications. (original dual point distributor and everything) Does it have a radio noise suppressor attached to coil??? I've seen this go bad also and cause the same problems..........Paul