spark seems weak

[Budnicks]

great thread I love a great debate...LOL...

 

[67 B-body]

great thread I love a great debate...LOL...

I never expected a debate myself..... I just KNOW what the results will be if I perform that simple test / task...... It just happens....

 

[440roadrunner]

Wrong again I'm afraid...

I didn't try to belittle anyone, I simply stated you are incorrect. You don't SPEAK like anyone who has a degree in anything.

The discharge of a CD/ photoflash is EXACTLY relevant to what happens in a Mopar ECU/ points fired ignition. The coil stores energy, discharges the field, and charges the cap. The cap discharges to the coil, and the two oscillate. THIS IS AN EASY TO PROVE FACTOID

The parallel IS that the cap stores energy and helps the coil to BUILD THE SPARK

For any of you readers who DO NOT BELIEVE this is true, and happen to have ANY engine which runs a points fired system, simply remove the condenser and see how well it runs. Uh.....It won't.

I'm not trying to impress anyone. I'm simply trying to explain that you CAN NOT CHECK A COIL under what might be called "simulated operating conditions" without a condenser/ capacitor. It simply will not build the spark as it does when installed in the system.

I think the words of your post speak for themselves. You are now trying to tell me I'm the troublemaker, when you keep insisting on posting incorrect information. I haven't called you any names, or belittled you in any way. I'm simply telling you that your statement about testing a coil IS NOT RELEVANT.

 

[bigmanjbmopar]

This is what I diagnosed this morning. With the key turned on, I'm only getting a little over 6 volts to the coil. When disconnected from the coil, I get 13 volts at the positive lead. I scraped all the grounds to bare metal. I have good continuity from coil negative back to the box and from the box frame to engine ground, but open between the coil negative and engine (body) ground (with key on). This leads me to believe that the control box is faulty, maybe fried it by using Accel coil? Now I realize I skipped a step and will check from the box terminal through the box to ground. The box is new but 30 plus years old.

Ha! I called it....:hello2: well at least for now until he proves the control box was bad by replacing it :headbang:


And debating? what's up with all the hate man?:thatswck: chill bro's it will be ok, the man will take in all your expertise and absorb it no need to fight about it when he finds the problem and hopefully reports back then we can see who gave the closets advice without having to produce a novel and cut down 20 trees
:moparts ghost:








Here just stare at this for awhile and relax

:downtown::downtown::downtown::downtown::downtown::downtown::downtown::downtown::downtown:

 

[67 B-body]

I didn't try to belittle anyone, I simply stated you are incorrect. You don't SPEAK like anyone who has a degree in anything.

The discharge of a CD/ photoflash is EXACTLY relevant to what happens in a Mopar ECU/ points fired ignition. The coil stores energy, discharges the field, and charges the cap. The cap discharges to the coil, and the two oscillate. THIS IS AN EASY TO PROVE FACTOID

The parallel IS that the cap stores energy and helps the coil to BUILD THE SPARK

For any of you readers who DO NOT BELIEVE this is true, and happen to have ANY engine which runs a points fired system, simply remove the condenser and see how well it runs. Uh.....It won't.

I'm not trying to impress anyone. I'm simply trying to explain that you CAN NOT CHECK A COIL under what might be called "simulated operating conditions" without a condenser/ capacitor. It simply will not build the spark as it does when installed in the system.

I think the words of your post speak for themselves. You are now trying to tell me I'm the troublemaker, when you keep insisting on posting incorrect information. I haven't called you any names, or belittled you in any way. I'm simply telling you that your statement about testing a coil IS NOT RELEVANT.

:BSMeter:

Whatever man...

 

[nothingbutdarts]

Did you get it running???

 

[moparbud66]

Wow, I started one heck of a thread and it great to read the debates. Back to the diagnosis, I went out this morning, plugged in the control box, turned on the key and put my meter leads between the coil negtive lead and body ground and it is open. I'm still thinking the box is faulty.

 

[1971RR]

I just replaced the ignition system on my 71 383 with a Mallory Unilite and related paraphernalia. With my key in the "on" position I get roughly 8v at the coil, which is what I was told I should get (stock or otherwise). One of the kickers was the type of coil used. If I used a coil with a resistance of 1.1 or 1.4ohm or higher (cant remember which one) I could bypass the resistor, 1.4/1ohm or less, I needed the resistor. My coil is high resistance so I bypassed. If I used the low resistance and bypassed the resistor I supposedly would nuke the ignition module in the distributor. And the high resistance coil with resister would create a low voltage issue. I also polished all grounds too for what its worth (the car sat forever, literally...well almost). I can reach through the window and bump the key on a cold day and she fires right up into high idle. Now if I could only figure out why she is a bitch to start after she is warmed up....

I guess in a long-winded kind of way is that I'm saying your coil could have toasted your ignition box...just tossing it against the wall to see if it sticks.

 

[moparbud66]

I just ordered the upgraded (and chromed!) box from Summit. I'll have it tomorrow and hopefully can put this thread to rest. Thanks to all those who responded and I know we all had some informative reading here in the last several days. I love this site, it has been very helpful.

 

[nothingbutdarts]

Are you still going to run the Accel coil?

 

[moparbud66]

I may try a stock coil to begin with although it is off a points system. My Accel coil is stock size (not that huge one) and I really did not think it would cause any problems. I'm confused about the resistor that 1971RR was talking about. Ballast resistor? Anyway, I ordered the box from Summit at 2 PM EST yesterday and my wife called me at 10:30 this morning and told me that my order from Summit had arrived! Could this be the long awaited day?

 

[Budnicks]

There are a couple of the coils from Accell that aren't very good, especially for street driving or long term usage, in there own notations they say, "not for more than 30 minutes of continuous operation", not knowing what coil you actually have, just putting it out there... MSD Blaster 2 is a great choice... bad/faulty cracked broken shreded wore out wiring, bad or insufficient ground, I've had a few box's that needed to be grounded better, bad ECU box, wrong possibly cracked tower & or bad coil, wrong ballast resister rating for the ignition system, bad or weak pick-up in distributor, could be any or a combination of all of them... Double check every thing... Good luck keep us posted....

 

[69Bee]

...You cannot test a coil by the method indicated. It WILL make a spark, but NOT a good spark WHY is that? Because these types of ignition systems MUST HAVE a condenser (capacitor) in the circuit. If you for example, remove the condenser from a points type distributor, the car generally will not start. The Mopar ignitions basically have a condenser built into the box...

The information in this paragraph is incorrect.

1) The condensor provides a temporary storage of the current so that the points do not burn.

2) The condensor does NOT need to be in the circuit for the ignition to work.

3) Mopar ignition boxes do NOT have a condensor built in for this purpose since the ignition box is merely a transistor (switch) that will trigger from the pulse generated buy the pickup in the dist. The currents here a much lower that an old point system.

 

[moparbud66]

Thanks Budnicks for the illustrations, that will help tremendously. I installed my pretty new box but to no avail. Now I will use the diagram to double check the wiring. Again, everything (including the harness) is new.

 

[SwedCharger67]

I'm still waiting to hear my newly rebuilt 440 run for the first time. Everything has been checked and double checked but she won't start. I pulled number one plug out and grounded it and it gets a small orange spark but nothing that looks like it will knock you on your butt or fire under compession. I have a NOS ignition box and electronic distributor, new forward conversion harness and new Accel coil, wires and plugs. Any ideas???

My guess is that you have a mismatch between the ignition box and the Accel coil. The ignition box must be able to drive the current that the coil requires, otherwise the spark will be weak.

 

[Big Sugar]

isolate the coil remove the tach sendor wire off the coil and anything else you have tied into the coil wires. you may want to open uo the engine harneness and recheck all the wiring within make sure all wires look good and any old wiring (unused is removed) keep your ignition wiring in a seperate bundle it'll help you source a problem if your stuck on the road.

I spent two days this summer with the same condition...after all the nonsence and replacing everything fron the ECU ,Coil, reloctor, Cap , Rotor, Plugs....turned out to be a short in the tach....66 Charger, with a updated tach.

Good luck

Ron

 

[moparbud66]

I've left the car alone for a while, but was recently going through some of my old pictures and came across an underhood picture of a 1973 Cuda I had that someone had put a 440 into. There is a condenser attached to one side of the 4 pin ballast resistor in the pic. and that car ran fine. I was only into that car for 2 grand (1991), I should have kept it. I wonder if there is any relevance to what I am experiencing currently. I am in the process of a carb/manifold swap so can't attempt to fire up anyway. Talk about digging up an old grave......