Dizzy Smoking???

[Anonymous]

First, thanks to all for the great posts on hooking up the Duraspark II.

I do, however, seem to have a problem. I installed a Duraspark II dizzy from a 1980 Mustang. I also used the GM HEI module and a TFI coil (as recommended on gofastforless.com).

I connected the Purple wire from the dizzy to the C pin on the module, the orange wire to the W pin on the module and finally connected the black dizzy wire to the the attaching screw into the aluminum heat-sink.

http://www.gofastforless.com/ignition/tfi.htm

When I went to start the car, the dizzy began smoking and the ground wire (black) burned through at the distributor.

What caused this? The ground wire did have some damage (missing insulation) prior to installing, although it would seem that a ground wire could be bare with no problems?? Why would there have been current flowing through the ground that would result in it's frying??

Did I hook something up wrong? Can the aluminum heat-sink be used to ground, or should I find another location?

I picked up another dizzy, from an '84 Fairmont, but want to make sure that the wiring is correct prior to trying it. Any help would be appreciated...

 

[Anonymous]

Nobody can help?? Does it at least look like it's wired right?

Can I ground to the aluminum heat sink??

LazyJW, I know that you did this set up...

Thanks..

 

[Anonymous]

well I dont know... but I would not ground at the heatsink, I grounded mine down by the horn on some random bolt

 

[fordconvert]

From your first post it looks like you may have it hooked up wrong, but I may have misunderstood.

One end:
Module G to dizzy purple
Module W to dizzy orange
(had them reversed corrected 10/4 )

Other end:
Module B to +12 key on/start source and + side of coil
Module C to - side of coil (this is not connected to ground anywhere)
Module case to dizzy black and other good ground to be sure

Fuses are good, mine with a blaster 2 coil seems to draw about 3 amps. Im running a 10 amp fuse because I know the wires can handle at least 10 and I have not gone to look for a smaller one.

On mine I ran a black ground wire along with the orange and purple from the dizzy to the module and from the module to a body ground screw with other screws. At the module I crimped both ground wires to one lug and put it under one of the module mounting screws. I have the module and the heat sync tywraped to the cross brace thing. No smoke on mine.



Perhaps you are missing your body to engine ground strap? Most people seem to forget to reinstall it when they pull the motor. Its possible that the ground wire from the dizzy to the body (where you mounted your module) is a better ground than some other one so there is more than the igniton system grounding through it.

 

[Anonymous]

Thanks guys,

fordconvert.. you said that W goes to purple? gofastforless.com says that W goes to orange and G goes to purple?? In my original post I said the purple was to C, but that was a typo. I've got purple to the G pin. I'll have to check the engine ground strap, I hadn't thought of that..

Is it necessary to ground the module, or can I just ground the dizzy straight to another location as 64falcon200 did?

 

[MustangSix]

The module must be grounded, either by screwing to a chassis ground or providng a grounding cable.

 

[fordconvert]

I had it wrong in my post (fixed it now). That was the way I had mine hooked up at first. It runs like that but you have a very narrow range of timing because it fires between the terminals on the cap. My first clue should have been I had to rotate the dizzy almost 1 terminal from where I expected it to be.

To add to what MustangSix said about the module ground.... Most of the modules have a metal tab or metal rivet looking thing on one of the holes (usually the one on the B & C side, this is the best place to hook up the ground so you dont have to count on it grounding through the base to the heat sink. Make sure you use some of the white heat sink compound between the module and the sink. If your module didnt come with it you can get a little tube at Radio Shack for about $3. Most of the parts store guys dont know what is and since its not on the car list in the computer they cant even order it for you.

Avoid the $20 or less modules, it seems to a degree you get what you pay for. I have only ever known of one GM module failing. I went through 3 WELLS ones on one car in about a month before I got smart enough to buy a differnt brand. The best for me have been GM and Standard. The good ones seem to be $35 ish. Accell and Mallory also make them, not sure on the cost.

 

[Anonymous]

Thanks again, It looks like its hooked up right. I'll run an additional grounding wire from the module to the frame. I guess (I hope) the problem was with the damaged ground wire on the first dizzy..

I guess I just didn't expect there to be enough current in the ground wire to burn it in half??

Thanks for the help, we'll see what happens with dizzy #2..

 

[addo]

Can you not work from first principles to get it sorted? Two wires into the module are from the inductive pickup. Two wires from the module go to the coil - one also is connected to the positive 12V supply. One of the screw eyes is to ground (larger bushed one). If you get the inductive pickup wires crossed it will probably run but not so happily...

Check you've not got a crushed and shorted wire in the dizzy pickup. To smoke it up suggests such a problem.

Lack of adequate heatsinking or conductive grease will hasten failure of the module.

Regards, Adam.

 

[Lazy JW]

...What caused this? The ground wire did have some damage (missing insulation) prior to installing, although it would seem that a ground wire could be bare with no problems?? Why would there have been current flowing through the ground that would result in it's frying??
...

If the module is not well-grounded, the primary current will attempt to go to ground through the next-easiest route. In your case, it went through the black wire to the distributor. Since there was already some damage to this wire, I suspect that it had a higher-than-normal resistance but still low enough to allow sufficient current flow to heat things up a bit.

Normally, with a low-resistance connection, the vast majority of the voltage drop occurs INSIDE the coil, right where you want it. But with a poor ground connection the resistance at the wire may well have been nearly equal to the impedance of the coil, causing at least half of the voltage drop to take place at the wire. POOF!

Double, triple check your connections, and remember, there is NO SUCH THING as TOO MUCH GROUND!

I wired mine exactly like the picture on www.gofastforless.com and it works great.
Joe

 

[Stubby]

Electric things have magic smoke. The magic smoke makes them work. Every time you let the magic smoke out they quit working.

 

[fordconvert]

I agree with what Joe said as the possible cause.

Just to add more thoughts and or questions that may not be the issue here.....

Does your - battery cable go to the body or engine?

On my 66 the - battery cable goes to a bolt on or near the front of the head. I didnt see any engine to body strap so I added one. I assume this was the orignal setup since by far the largest load was the starter. If there was no strap to the body what else does or could things ground through? Motor and transmission mounts are both rubber? Are there some ground wires in other harnesses? Where did the orignal ground strap go?

 

[addo]

Mine is at the rear, from head to firewall. That's an Oz roundbody.

 

[Anonymous]

OK, so let me get this straight..

If I'm hearing you all right, I've got it wired correctly (at least in principle).

There's no such thing as too much ground, so I'll add a ground from the module to the frame. Also, I can't find a ground strap, so I'll add one of those from the engine to the body.

And finally, I need to figure out a way to keep the magic smoke from coming out... Maybe the new distributor will do that..

Thanks for the help guys, I'll give it a shot this weekend. A small fire can't be that devastating can it?

 

[Anonymous]

OK, I replaced the dizzy with a new one. This time there is no damage to the ground wire. I added a ground strap from the valve cover bolt to the firewall. I added an additional ground wire from the module/dizzy ground to the radiator support.

Results....Still smoked. This time I stopped before it burned through, although I'm sure it still might.

Here's the current wiring.

1) the only wire connected to the battery is the lead to the solenoid. I disconnected all other wires from the solenoid.
2) I attached a jumper, straight from the battery to the "I" on the solenoid, thereby bypassing the entire wiring harness. This should eliminate any potential for bad grounds elsewhere, correct???
3) I used a remote starter from the B+ on the solenoid to the "S".
4) I grounded the B- directly to the ground on the solenoid.

First, I left the starter side of the solenoid disconnected and tested. Solenoid "clicked" when using the remote starter and all voltage and resistance readings appeared normal.

Next, I tested continuity (sp?) throughout the vehicle to ensure that my grounding strap was actually grounding. I recorded 0 ohms, indicating continuity. This included the grounding at the firewall to the grounding at the distributor and the grounding at the distributor to the grounding at the solenoid. All readings were 0.

5) I connected the solenoid to starter cable.

Using the remote starter, everything appeared OK at first (the first 2 trys), then the distributor began smoking again at the dizzy side of the black wire...

Anyway, I can't figure out why the problem? Why is the current from the starter going to ground through the distributor? Why is the current so great that it is smoking the wire? Why isn't the grounding strap the path of least resistance?

Would grounding the distributor to a bolt on the engine prevent this? I would assume that all current would then run through the grounding strap.

Can I assume that there is not a bad ground elsewhere since I have eliminated the entire wiring harness??

Anybody???? Please help. I'm at a loss...

 

[Lazy JW]

I'll give it another shot. Having re-read your posts three times I see no reference to the coil connections. If the coil is hooked up correctly then I think the coil itself must be internally shorted.

My reasoning is thus; if the coil is good, you should be able to run it with breaker points (they won't last long). Breaker points would give a zero-resistance to ground, the coil would draw heavy current but the voltage would be dropped across the coil and would not fry the wire. A healthy spark would be generated when the points open.

The module/DS2 distributor simply cannot create more of a "short circuit" than the breaker points in my above example. Therefore, SOMETHING has to be drawing excess current. The coil is in series with the module, so it must have lower-than-normal resistance.

Or the coil is wired incorrectly from the source.
Joe

 

[fordconvert]

Is it possible the module is shorted from earlier problems? What happens if you crank the engine without the power wire hooked to the module& coil? At least this would eliminate the ignition system as part of the problem. To burn up that size wire has to be a non fused or larger size fused circut. A 20 amp or less fuse will blow fairly easy if there is enough draw to melt a 14-16 gauge wire. It would seem that you have enough grounds now that its not something else grounding through the dizzy.

 

[fordconvert]

Just to clarify the ign wires, Dizzy purple and Orn go directly to the module W & G. Dizzy black goes to ground anywhere. Coil gets + to the B terminal on the module and then to the 12 source. Coil - goes to the C on the module and no where else no ground or anything. If this was connected to ground at any time it could have fried your coil and maybe the module. Module gets a ground wire to one of the mounting screws (the one with the metal clip or rivet even tho it should ground through the heat sink).

 

[Anonymous]

Thanks for helping guys.

The ignition system is not connected to any power source. The coil is a TFI coil and the red wire is connected to the B on the module. The green wire is connected to the C on the module. Again, there is no power to the coil at this point. I was isolating the solenoid and starter, so I'm assuming that I could remove the coil and the problem would be the same??

This is the first attempt to start this car, so I don't know whether or not using the points would make a difference.

The only "hot" wire is the one from Battery + to starter. I'm thinking from reading other posts that the problem is that my battery is grounded to the body. It looks like the grounding strap is not large enough to ground the starter and so the excess is travelling to ground through the dizzy ground.

I'm going to try again with grounding the Battery - to the engine block. I would hope that this would make the path of least resistance the 4 guage cable back to the battery and take the load off of the dizzy ground.

What do you guys think about that theory?

 

[Anonymous]

That looks like it!!

I grounded B- to the block and... NO MORE SMOKING!!

I don't know why that I assumed it would ground to the frame/body??

Anyway, it's not running yet, but it turns over without burning up....A major improvement.

Thanks to Joe and TJ for staying with me..