Engine cuts out and stalls while driving.

[MYBAD79]

Sweet, that's a cheap and easy fix.
by the way, I have a working HEI dizzy and another one that is missing the module and the cap sitting on the shelf... had it turned out to be a distributor problem I could have send you either one or both if you needed parts...

 

[enkeivette]

I appreciate that, but I've got my OEM HEI in the garage under my L48. I used it a few months ago to drive around when Bird was customizing my dist.

 

[MYBAD79]

So you have a spare dizzy ... I guess swapping distributors wasn't all that bad of an idea afterall ... :lol::lol:

 

[enkeivette]

That was my plan when this happened. But before I pulled it out I saw the melted wire.

 

[big_G]

Seems strange that 1 spark plug wire would completeky kill the engine. Never seen that before.

 

[73 Mike]

Seems strange that 1 spark plug wire would completeky kill the engine. Never seen that before.

I am surprised as well. One burned wire will make it idle rough and run rough, but I'm surprised it would cause the engine to cut out. Although an apples to oranges comparison, take one wire off the spark plug on another car and drive it around. You'll wonder what's wrong but you'll still get to where you're going.

 

[mrvette]

Seems strange that 1 spark plug wire would completeky kill the engine. Never seen that before.

I am surprised as well. One burned wire will make it idle rough and run rough, but I'm surprised it would cause the engine to cut out. Although an apples to oranges comparison, take one wire off the spark plug on another car and drive it around. You'll wonder what's wrong but you'll still get to where you're going.

Try two of them, drove me krazy for several months....nothing at night, nothing even with WINDEX sparyed at night....but #5&6 drove me stupid...I was just going nutz leaning over the fender on a BRIGHT sunny day...and that mofo snapped at me, right in front of my nose.....true story....:flash: 8 Jacobs plug ends later it's fixed....

I dunno what is SO difficult about making headers that don't burn plug wires....

:bonkers:

 

[Arthur Brown]

very interessting topic and I'm glad you found what's wrong. Inexpensive as well. I read this thread at cf, this Turtle guy is a jerk.

 

[enkeivette]

So I got so tied up with a moron that parades around in a 165hp POS 75 C3 (who is proud of it, naming himself Turtle and for some reason 'races' it) that I almost forgot to follow up over here.

This was my Dad's (electrical engineer) theory as to what happened. He speculates that the voltage needs to build up when you're supplying a very small amount of current for it to build up the voltage high enough to jump the spark plug gap. But when there is a dead short (on the header), the voltage cannot build up because it is constantly draining (just on that prong of course) and by the time it fails it has drained the coil which is why it didn't have enough power transfer capability to keep the voltage high enough for the other spark plugs.

To phrase this in a way that would piss Turtle off: The resistance of the air is almost infinite (before it ionizes) while the resistance of the copper core melted to the grounded header is comparatively almost nothing so when the spark plug wire is shorted out, the voltage cannot build up in the coil.

 

[big2bird]

This was my Dad's (electrical engineer) theory as to what happened. He speculates that the voltage needs to build up when you're supplying a very small amount of current for it to build up the voltage high enough to jump the spark plug gap. But when there is a dead short (on the header), the voltage cannot build up because it is constantly draining (just on that prong of course) and by the time it fails it has drained the coil which is why it didn't have enough power transfer capability to keep the voltage high enough for the other spark plugs.

To phrase this in a way that would piss Turtle off: The resistance of the air is almost infinite (before it ionizes) while the resistance of the copper core melted to the grounded header is comparatively almost nothing so when the spark plug wire is shorted out, the voltage cannot build up in the coil.

I believe the only way this could occur would be the added equation of spark scatter in the cap.

 

[mrvette]

This was my Dad's (electrical engineer) theory as to what happened. He speculates that the voltage needs to build up when you're supplying a very small amount of current for it to build up the voltage high enough to jump the spark plug gap. But when there is a dead short (on the header), the voltage cannot build up because it is constantly draining (just on that prong of course) and by the time it fails it has drained the coil which is why it didn't have enough power transfer capability to keep the voltage high enough for the other spark plugs.

To phrase this in a way that would piss Turtle off: The resistance of the air is almost infinite (before it ionizes) while the resistance of the copper core melted to the grounded header is comparatively almost nothing so when the spark plug wire is shorted out, the voltage cannot build up in the coil.

I believe the only way this could occur would be the added equation of spark scatter in the cap.

As the coil is totally DEenergized after the spark, with little to no ringing afterwards due to a back biased diode in the circuit, called a damper diode in olde tyme TV's....the coil is waiting for the next order to energise then when it opens you get that spike again for the next cylinder, that spike forms when the 'points' or sending unit opens the circuit on the primary side....those capacitors there form a tuned circuit to maximize that spike on the secondary, and help with further coil ringing before the next cylinder fires....

damping or shorting ONE cylinder wire should not affect the firing of the other 7 cylinders, UNLESS there is another shadowy type fault lurking...such as temperature, or like Bird says, something funky in the cap/rotor area....

I have worked in pulse field electronics quite a bit, it's how those walk through metal detectors at airports, nuky plants, jails work......

same shit, different application, in other fields that spike is a bit of a pain and something to be controlled if not eliminated

I would love to have seen that failure mode on my scope....

:bonkers::beer::flash:

 

[69427]

So I got so tied up with a moron that parades around in a 165hp POS 75 C3 (who is proud of it, naming himself Turtle and for some reason 'races' it) that I almost forgot to follow up over here.

This was my Dad's (electrical engineer) theory as to what happened. He speculates that the voltage needs to build up when you're supplying a very small amount of current for it to build up the voltage high enough to jump the spark plug gap. But when there is a dead short (on the header), the voltage cannot build up because it is constantly draining (just on that prong of course) and by the time it fails it has drained the coil which is why it didn't have enough power transfer capability to keep the voltage high enough for the other spark plugs.

To phrase this in a way that would piss Turtle off: The resistance of the air is almost infinite (before it ionizes) while the resistance of the copper core melted to the grounded header is comparatively almost nothing so when the spark plug wire is shorted out, the voltage cannot build up in the coil.

I have to respectfully disagree with the explanation you provided, but I'm speculating the error is in your understanding of electronics and inductive circuits, not your dad's actual words to you.
An after-the-fact question. Did the engine restart by just moving the key to START, or did you power off (key to OFF) prior to the restart?
Okay, I guess a second question. I don't recall getting an answer to whether there is/was an external CD box hooked to the distributor.

 

[mrvette]

So I got so tied up with a moron that parades around in a 165hp POS 75 C3 (who is proud of it, naming himself Turtle and for some reason 'races' it) that I almost forgot to follow up over here.

This was my Dad's (electrical engineer) theory as to what happened. He speculates that the voltage needs to build up when you're supplying a very small amount of current for it to build up the voltage high enough to jump the spark plug gap. But when there is a dead short (on the header), the voltage cannot build up because it is constantly draining (just on that prong of course) and by the time it fails it has drained the coil which is why it didn't have enough power transfer capability to keep the voltage high enough for the other spark plugs.

To phrase this in a way that would piss Turtle off: The resistance of the air is almost infinite (before it ionizes) while the resistance of the copper core melted to the grounded header is comparatively almost nothing so when the spark plug wire is shorted out, the voltage cannot build up in the coil.

I have to respectfully disagree with the explanation you provided, but I'm speculating the error on your understanding of electronics and inductive circuits, not your dad's actual words to you.
An after-the-fact question. Did the engine restart by just moving the key to START, or did you power off (key to OFF) prior to the restart?
Okay, I guess a second question. I don't recall getting an answer to whether there is/was an external CD box hooked to the distributor.

I agree about an interpretation problem in there somewhere....

:beer:

 

[enkeivette]

So I got so tied up with a moron that parades around in a 165hp POS 75 C3 (who is proud of it, naming himself Turtle and for some reason 'races' it) that I almost forgot to follow up over here.

This was my Dad's (electrical engineer) theory as to what happened. He speculates that the voltage needs to build up when you're supplying a very small amount of current for it to build up the voltage high enough to jump the spark plug gap. But when there is a dead short (on the header), the voltage cannot build up because it is constantly draining (just on that prong of course) and by the time it fails it has drained the coil which is why it didn't have enough power transfer capability to keep the voltage high enough for the other spark plugs.

To phrase this in a way that would piss Turtle off: The resistance of the air is almost infinite (before it ionizes) while the resistance of the copper core melted to the grounded header is comparatively almost nothing so when the spark plug wire is shorted out, the voltage cannot build up in the coil.

I have to respectfully disagree with the explanation you provided, but I'm speculating the error on your understanding of electronics and inductive circuits, not your dad's actual words to you.
An after-the-fact question. Did the engine restart by just moving the key to START, or did you power off (key to OFF) prior to the restart?
Okay, I guess a second question. I don't recall getting an answer to whether there is/was an external CD box hooked to the distributor.

I agree about an interpretation problem in there somewhere....

:beer:

Yeah sorry guys, I typed that paragraph quickly as he rattled off his theory to me.

External CD box: I don't think so. There is only an MSD HEI, no external coil or anything like that. There is a tach filter that my Dad built from scratch that works great, other than that nothing that I can see.

Bird, what is spark scatter?

 

[69427]

Yeah sorry guys, I typed that paragraph quickly as he rattled off his theory to me.

External CD box: I don't think so. There is only an MSD HEI, no external coil or anything like that. There is a tach filter that my Dad built from scratch that works great, other than that nothing that I can see.

Bird, what is spark scatter?

I still need an answer to my after-the-fact question above.

 

[enkeivette]

I still need an answer to my after-the-fact question above.

Don't remember. But since you have to press down that lock tab to move the key all the way back, I probably didn't.

 

[69427]

I still need an answer to my after-the-fact question above.

Don't remember. But since you have to press down that lock tab to move the key all the way back, I probably didn't.

My last question, because I'm growing tired of asking. I'm assuming you don't need to press down on a tab just to turn the engine off, but to move it to the lock position. Is that correct, and did you turn the switch to the off (not lock) position prior to restarting?
This is a technically pertinent question, and any electrical engineer can verify the usefulness of this question.

 

[enkeivette]

I still need an answer to my after-the-fact question above.

Don't remember. But since you have to press down that lock tab to move the key all the way back, I probably didn't.

My last question, because I'm growing tired of asking. I'm assuming you don't need to press down on a tab just to turn the engine off, but to move it to the lock position. Is that correct, and did you turn the switch to the off (not lock) position prior to restarting?
This is a technically pertinent question, and any electrical engineer can verify the usefulness of this question.

My last answer, because I'm getting tired of responding. I DON'T REMEMBER. But probably not. Did you not read my response? This happened a few months ago. I'm just having fun speculating with you guys, I'm really not looking for any help from you so don't get testy.

 

[69427]

I still need an answer to my after-the-fact question above.

Don't remember. But since you have to press down that lock tab to move the key all the way back, I probably didn't.

My last question, because I'm growing tired of asking. I'm assuming you don't need to press down on a tab just to turn the engine off, but to move it to the lock position. Is that correct, and did you turn the switch to the off (not lock) position prior to restarting?
This is a technically pertinent question, and any electrical engineer can verify the usefulness of this question.

My last answer, because I'm getting tired of responding. I DON'T REMEMBER. But probably not. Did you not read my response? This happened a few months ago. I'm just having fun speculating with you guys, I'm really not looking for any help from you so don't get testy.

Chill out, dude. I know a hell of a lot more about ignition systems than you do, and I foolishly was trying to help. I won't make that mistake again. I asked a simple question, multiple times, and you seem to have a difficult time understanding simple English. Unless all your law school books are written in Swahili or something, I'd be a little concerned about this English comprehension difficulty you seem to be exhibiting.
I'm not a big fan of Turtle's manners around people, but I'm starting to understand his outlook on this particular thread.
I'm outta here.

 

[enkeivette]

I still need an answer to my after-the-fact question above.

Don't remember. But since you have to press down that lock tab to move the key all the way back, I probably didn't.

My last question, because I'm growing tired of asking. I'm assuming you don't need to press down on a tab just to turn the engine off, but to move it to the lock position. Is that correct, and did you turn the switch to the off (not lock) position prior to restarting?
This is a technically pertinent question, and any electrical engineer can verify the usefulness of this question.

My last answer, because I'm getting tired of responding. I DON'T REMEMBER. But probably not. Did you not read my response? This happened a few months ago. I'm just having fun speculating with you guys, I'm really not looking for any help from you so don't get testy.

Chill out, dude. I know a hell of a lot more about ignition systems than you do, and I foolishly was trying to help. I won't make that mistake again. I asked a simple question, multiple times, and you seem to have a difficult time understanding simple English. Unless all your law school books are written in Swahili or something, I'd be a little concerned about this English comprehension difficulty you seem to be exhibiting.
I'm not a big fan of Turtle's manners around people, but I'm starting to understand his outlook on this particular thread.
I'm outta here.

You're the one that said "youre getting tired of asking" and I need to chill out? I wasn't ignoring you, I just read fast and missed your 2nd ques. It was not a comprehension problem. But you know that, you were just looking for a low blow.

And I'll bet you do know more about electrical systems in cars than I do. Good for you. :drink: Like I said, don't need help, just speculating the science of a problem that has already been resolved.

As far as understanding Turtle's point of view, I hope you don't. He's a moron. Just because you're mad at me doesn't mean you should identify with a moron, that just looks bad on you. And from what I can remember about you you're an intelligent guy.