Topic: Yet MORE coil problems...

[jfrabat]

About a month ago, my dad took the Jeep out for a stroll, and the Coil died on him.  He took his boat mechanic with him, changed the coil (I ALWAYS carry spares), and he was on his way.  He proceeded to take it to an electical mechanic, and he tested several things, and they all checked out OK (voltage being received by the coil from the alternator, if there was any electricity being received by the coil when the key was turned off, short circuits, etc.).  He told my dad he thought the issue was excesive heat.  Today, we were driving back from Panama to Costa Rica, and the coil died again.  Again, I changed it, and we were on our way, but this is REALLY getting tiring.  When I changed the coil, obviously the whole assembly (coil, bolts, nuts and mounting plate) were too hot to touch.  I am now considering buying a Flame Thrower coil with mount and simply installing the coil away from the engine (in the firewall, as high as possible).  What do you guys think about this?  Pros/Cons?

For your reference, this is what I am planning on getting:

While it's the perfect coil to go with the PerTronix Ignitor breakerless ignition, our 40,000 volt Flame-Thrower canister coil can benefit virtually any distributor type inductive system. Its higher voltage allows larger spark plug gaps for added power, smoother response and better fuel economy. These coils are internally resisted so they are compatible with many ignition systems.

Our oil filled coils offer great heat control for street driven vehicles, while our epoxy filled coils provide superior winding support for high vibration environments in offroad vehicles and boats.
 
Features
 •40,000 volts
•Available chrome plated or black for that "stock look".
•For use with inductive ignition systems.
•1.5 or 3.0 Ohm primary resistance values available.
•Legal in all 50 states and Canada. (C.A.R.B. E.O. #D-57-10)
•Warranty: 90 Days

By the way, do I want 1.5 or 3.0 Ohm resistance?  And do I want oil filled or resine filled?  I am thinking 3.0 Ohm resin filled, but not sure...

[jfrabat]

Oh, and I would mount it with this:

[sharpxmen]

something else is going on, all other YJs including mine have the coil in the same spot - it's got to be at least 4 coils you toasted so far.

[grumpygy]

Mine went right after I replaced mine with a flame thrower 3.0 ohms.  But my problem was I did not match the Ohms.  Mine got hot too so hot that the smoke from it was burning my eyes.  I thought it was either mine or a truckers clutch going.  Then it started to misfire.

Went with the performance Distributor coil and have not had one problem since.

The topic when I talk about it.

http://4bangerjp.com/forums/index.php/topic,9947.0.html

And one more that talks about the Performance Distributor stuff.

http://4bangerjp.com/forums/index.php/topic,29.0.html

[aw12345]

Are you using coils that are supposed to use a ballast resistor? Some cars used a separate ballast resistor, others used a resistor wire from the ignition to the coil.
For some reason your coil is drawing to much current, which is what cooks it

[jfrabat]

I have actually toasted more than 6, including 2 or 3 screaming demons from performance distributors, and Accel coil, some cheap coils, and some original replacements...  whatever is causing this, it is getting old quick!  Any ideas on what to do are greatly welcome!  I agree that changing the coild to another location will cure the symptom and not the problem, but I need some solution FAST!  Any ideas on what to do?

[sharpxmen]

I have actually toasted more than 6, including 2 or 3 screaming demons from performance distributors, and Accel coil, some cheap coils, and some original replacements...  whatever is causing this, it is getting old quick!  Any ideas on what to do are greatly welcome!  I agree that changing the coild to another location will cure the symptom and not the problem, but I need some solution FAST!  Any ideas on what to do?

are these coils going dead while driving (engine running) or just failing to start after the vehicle has been turned off and sitting for a while?

EDIT: and also, do you have an aftermarket alternator? if yes do this and let me know the result: pull the 2 terminal plug from the back of it and measure the voltage between each terminal and ground, let me know if any of the 2 has 12v on it - if that turns out to be the case there's a simple solution to your problem.

[aw12345]

are these coils going dead while driving (engine running) or just failing to start after the vehicle has been turned off and sitting for a while?

EDIT: and also, do you have an aftermarket alternator? if yes do this and let me know the result: pull the 2 terminal plug from the back of it and measure the voltage between each terminal and ground, let me know if any of the 2 has 12v on it - if that turns out to be the case there's a simple solution to your problem.

Wouldn't overcharging fry the ecm also? I have seen some ecm's die within minutes due receiving around 16 volts. I think a good starting point would be to just add a ballast resistor to the coil on the positive side and see what happens.
Also I am not at all a fan of aftermarket ignition products, most are overpriced unreliable junk. Stock coils on average will last well over 100.000 miles.
About the only other cause, could be to high a secondary ignition demand. My vote is for to high a primary current through the coil

[jfrabat]

The coils are dying with the engine running.  It starts as a little cough when accelarating (this last for a while), and then it just dies.  If I reinstall a fried coil, I get some more miles from it (after they cool down), which goes with the theory of heat being the culprit.  The voltage at the coil was measured with different electrical consumptions, and it was always between 13 and 14 volts (13.5V IIRC, but it could have been 13.8V; anyway, the guy said it was not that).

About the ballast resistor, what is it, where do you get it, how does it install, and what does it do? 

[sharpxmen]

Wouldn't overcharging fry the ecm also? I have seen some ecm's die within minutes due receiving around 16 volts. I think a good starting point would be to just add a ballast resistor to the coil on the positive side and see what happens.
[...] My vote is for to high a primary current through the coil

i wasn't thinking in regards to overvoltage - the ASD provides voltage at the alternator field and is controlled on the second wire by the PCM, if the voltage is present with the ignition off then the field is permanently connected and it would also have voltage at the ignition coil and the injectors - that was why i asked.

current is related to the voltage and impedance, if he's got the correct voltage and an OEM coil it should not have excessive current, but the ballast resistor is worth a shot, maybe something is screwy with the PCM, i don't know what's supposed to be on the coil driver inside the PCM (if it has a resistor or not and could be fried).

[jfrabat]

i wasn't thinking in regards to overvoltage - the ASD provides voltage at the alternator field and is controlled on the second wire by the PCM, if the voltage is present with the ignition off then the field is permanently connected and it would also have voltage at the ignition coil and the injectors - that was why i asked.

current is related to the voltage and impedance, if he's got the correct voltage and an OEM coil it should not have excessive current, but the ballast resistor is worth a shot, maybe something is screwy with the PCM, i don't know what's supposed to be on the coil driver inside the PCM (if it has a resistor or not and could be fried).

Would it also be worth a shot to tey to try to insulate the mount and/or the coil to reduce the heat, in case rhat is really the problem?

[jfrabat]

Bump...  would insulating the mount cause ignition issues?

[aw12345]

That could actually make it worse since the bracket will transmit heat to the engine block. Sharp could be on to something if the coil keeps getting power when the engine is off

[jfrabat]

That could actually make it worse since the bracket will transmit heat to the engine block. Sharp could be on to something if the coil keeps getting power when the engine is off

The mechanic in Panama checked for that, and there was no voltage with the ignition turned off...

[sharpxmen]

The mechanic in Panama checked for that, and there was no voltage with the ignition turned off...

if not the alternator maybe a stuck ASD relay, it could be acting randomly as in getting stuck once in a while, but to be honest i don't know that even if that's the case if it would cause the coil to go bad, the PCM shouldn't keep the ground on the signal wire (never checked that but just my common sense) - i'm out of ideas though