Burnt Coil = Mystery Smell

428street · #1 (**permalink**) 03-29-2009, 05:17 AM

ok, so I got lucky yesterday and then I got even luckier...

I did my normal take the car out of the garage warm it up and then move it down the bottom of my driveway because the boss doesn't like the smell to much. So being a law abiding, peace keeping husband I did that yesterday as well.

I get in the car, put it in reverse, hit the gas to back up and the car dies! Usually I have been able to get out of any situation rather quickly. I have been "learning" how to start the car as each car has it's own sweet spot of start-up routine. Well nothing I did worked and I had a gut feeling that there was something more serious.

As I am walking up my driveway a guy who I didn't know parks his car and comes over towards my car and introduces himself. He immediately asks what make the car is and I told him. Come to find out he is good friends with one of the "founders" years ago of ERA now living in Florida. Don't remember his name off the top of my head.

He knew very well of Peter's original car and his first replica. He thought this was his car! Then I had to explain to him that I absolutely loved the car but today was not a good day. I was stuck on the bottom of my driveway and the car would not start.

Now as many of you know I am a super detail guy but I am not any where near a "seasoned" mechanic. I know enough to be dangerous but thats about it. Well, he went back home, got his tester and ended up spending at least an hour with me troubleshooting. I learned a TON and now feel comfortable being able to troubleshoot if need be.

To make a long story short, we found the coil I had burnt out and tar coming out of the top. Luckily I had a used spare. Replaced it, and it fired right up. Now that is awesome. BTW, this guy has about 10-12 cars.

Ok, now for my question. Do I need a resistor? I did not have one and the guy said that this is probably the reason why this coil burnt. He said it is also probably the smell I was getting as well. Won't know until I go for a long drive but I'm fairly certain it was the problem.

I believe I spoke to Doug about needing a resistor and he said no. I have a Pertronix's ignition, stock coil, and distributor as back ground info..

Bob, electrical guys?

JBCOBRA · #2 (**permalink**) 03-29-2009, 06:34 AM

Hi 428street!
Congrats on fixing your baby. That must have been driving you nuts. And, as luck would have it, you didn't get stuck out on the road someplace.
I know my car has a ballast resistor. I am pretty sure they regulate how much juice goes to the coil. They are very cheap and easy to install.

Doug I · #3 (**permalink**) 03-29-2009, 06:36 AM

Do you need a resistor ? - this Doug is going to say "I have absolutely no earthly idea at all"

Glad your fix was an easy one.

Woodz428 · #4 (**permalink**) 03-29-2009, 09:45 AM

Most stock Ford coils have an internal resistor. It should say on the body. If it's not a stock Ford coil with an internal ballast it does need a ballast resistor in the power wire.

428street · #5 (**permalink**) 03-29-2009, 10:20 AM

I want to clarify, maybe I over exaggerated a bit. The top was not melted...the top was in tack, there was some black tar coming out of the crease where the mustard top meets the black cover....

patrickt · #6 (**permalink**) 03-29-2009, 12:01 PM

The Pertronix Flame-Thrower coil? No, you don't need a ballast resistor. Uhhh, you don't happen to have your coil mounted horizontally do you? (Meaning not having it straight up and down).

Why I asked -- If you have it mounted sideways, make sure it's the epoxy and not oil filled.
http://www.pertronix.com/prod/ig/fla...s/default.aspx

428street · #7 (**permalink**) 03-29-2009, 01:01 PM

I had the original small half-pint black/mustard top coil and it is mounted in the correct location, horizontially on top of the intake.

patrickt · #8 (**permalink**) 03-29-2009, 01:20 PM

Quote:

Originally Posted by 428street

I had the original small half-pint black/mustard top coil and it is mounted in the correct location, horizontially on top of the intake.

OK, if that is an oil filled coil and you have it mounted horizontally then that's most likely the problem. If you want it mounted horizontally then you gotta go with the epoxy "High Vibration" off-road jobs. Oil-filled coils leave air bubbles when mounted on their side and either short-out or overheat (or both).

428street · #9 (**permalink**) 03-29-2009, 01:26 PM

Ok, ? And I am not being a wise butt. I understand your thought process but why would Ford have designed the coil to sit on top horizontally? BTW, I have seen my share of people who have them mounted vertically on the block...now I know why. The Pertronixs does have one that is high vibration and I think silicone filled...

patrickt · #10 (**permalink**) 03-29-2009, 01:38 PM

Quote:

Originally Posted by patrickt

OK, if that is an oil filled coil and you have it mounted horizontally then that's most likely the problem. If you want it mounted horizontally then you gotta go with the epoxy "High Vibration" off-road jobs. Oil-filled coils leave air bubbles when mounted on their side and either short-out or overheat (or both).

I promise I'm not making it up.

MSD makes a big deal about it (I have mine mounted sideways on the intake as well) and sells their "Hi-Vibration" coil specifically for that purpose. I did a quick Google on the MSD site and found this chat thread from their tech support where the tech guys says "The oil is what cools the coil. When a oil filled coil is mounted side ways it tends to get hot and fail." https://www.msdignition.com/forum/showthread.php?t=1818 I'm also pretty sure the instructions for oil-filled coils always tell you not to mount them sideways.

428street · #11 (**permalink**) 03-29-2009, 01:51 PM

I don't think you are making it up at all...it makes a lot of sense....

patrickt · #12 (**permalink**) 03-29-2009, 01:52 PM

Quote:

Originally Posted by 428street

I don't think you are making it up at all...it makes a lot of sense....

Well, I've been known to make up shi*, at least according to my wife & kids.

428street · #13 (**permalink**) 03-29-2009, 02:16 PM

My wife thought this was funny....

strictlypersonl · #14 (**permalink**) 03-29-2009, 02:47 PM

The original street 427 had a ballast resistor, at least according to the wiring diagram. Don't ask me where they hid it. Not visible anywhere in my picture archive.

My recollection is that a resistor is preferred when using a Pertronix ignition module.

428street · #15 (**permalink**) 03-29-2009, 02:51 PM

I think the BR was located on the bottom right hand corner of the firewall...I'll call Doug and see if he has one in stock...thanks.

patrickt · #16 (**permalink**) 03-29-2009, 03:11 PM

Quote:

Originally Posted by strictlypersonl

My recollection is that a resistor is preferred when using a Pertronix ignition module.

Quote:

If converting from a point type ignition, remove any resistance wire, or ballast resistor that may have been previously used. If a resistance wire is present: replace the wire with a 12-gauge copper stranded wire. Most resistance wires begin at the engine compartment side of the fuse block. If a ballast resistor is present: remove the wires attached to both sides of the resistor. Connect all of the wires removed together at a single point. Isolate the connection from any grounds.

Source -- Flame-Thrower Instructions http://static.summitracing.com/globa...istributor.pdf

It couldn't hurt to just call the Pertronix tech guys though.

Ronbo · #17 (**permalink**) 03-29-2009, 05:25 PM

Nope, ballast resistors were only required on point ignitions as points could leave the coil continuously energized while the engine was not running and the key was still "on". By design electronic ignitions can't do this.

GM (starting around mid 60's) used a NiChrome wire from the firewall block to the coil so there was no visible resistor. Far as I can recall Ford and Chrysler used either a resistor or a built-in ballast in the coil.

Rick Parker · #18 (**permalink**) 03-29-2009, 08:27 PM

I think Ford prior to 1975 used a special kind of Wire that had a certain OHM resistance value "Per Foot". It was used from the + side of the coil to the 12 Volt switched hot source whether it was from the ignition switch or the fuse block. Once they introduced the 1st generation of electronic ignition the transistors began doing the work.

Dangerous Doug · #19 (**permalink**) 03-29-2009, 08:45 PM

So much for the "Taco Bell" theory. Glad to hear you figured it out.

DD

PANAVIA · #20 (**permalink**) 03-30-2009, 03:50 AM

We have had trouble with the repro "mustard-top" coils to the point where we will not use them. -- we use pertonix , MSD, mallory, motorcraft, or delco (if its a GM car) .