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Why do coils die?

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Thanks for all the advice-

A real quick, prelim. response form me.

I am unable to use any electronic testing devices.
Burned up two trying to learn how they function.
I am limited to a testing light for circuits.

The previous four burned up coils were purchased from
Western Auto, supposedly for a 1969 Triumph TR6.
The outside of the coil cans read 12V, no external
resistor required.

The Lucas Sport coil that burned up this morning was:

Part Number: DLB105 in a Lucas box.

The only coil for your British car that gives you a hotter spark and is still made by Lucas! With a 40,000 volt output it ensures effortless starts and a hotter spark which will help burn more mixture in the cylinder. Works with non-ballasted ignition systems only.

I'll go trace my wiring of the Power Block and be back later.

thanks again,

dale
 
All of those coils should be correct for your car.

The plot thickens......

"The only coil for your British car that gives you a hotter spark and is still made by Lucas! With a 40,000 volt output it ensures effortless starts and a hotter spark which will help burn more mixture in the cylinder. Works with non-ballasted ignition systems only."

Don't always believe the ad material either....
 
Dale
when you had the distributor rebuilt, did you have Jeff install an electronic ignition like Pertronix or some other replacement for the points?
If you have the original points, they may be set to be giving power to the coil for to long a percentage of time, which will cause the coils to heat up. This is the "dwell"
If you have an electronic unit, there could still be some sort of problem where is is powering the coil for to large a percentage of the time, which will cause it to heat up.
Since you have used different brands of coils, I think we can pretty much rule out the coil itself as the root cause. So that only leaves us with 1. the low voltage side (points / electronic ignition) or 2 the high voltage side, but since the engine runs, presumably the spark is reaching the plug, so the high voltage side would seem to be alright.
Let us know whether you have point or something else there.
 
Tinster said:
I am unable to use any electronic testing devices. Burned up two trying to learn how they function.
I am limited to a testing light for circuits.
Click to expand...

Just think we found something for Dave to do on his upcoming visit. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
Oh MY GOODNESS!
A working vacation?
What a novel idea.
You guys are so much help.
I'm gonna start booking holidays for you in your areas of expertise.
Anyone good with window installations (house I mean)?

Dave (Saturday Tinster)
 
Alec (Piman) may be onto something when he questioned what kind of voltage was coming out of your new alternator.
If the regulator inside the alternator is malfunctioning then it can crank out 20 volts or more which could be toasting your coil (if you haven't already done that while powdercoating)
When my alternator did this it eventually fried the battery.
I know you don't have a multimeter because 2 have burned out, but you can get the analog type with a needle instead of numbers for 20 bucks and that will tell the tale and they don't burn out as easily.
 
How do you burn out an ohm meter,especially an engineer?
 
Burning up an analog meter is easy (unless it's one of those high-end Simpsons with the circuit breaker). Just connect it to the wrong range, eg 12v when set to ohms or 120v when set to 12v.

Which is why I prefer digital meters, normally they are far more rugged both electrically and physically. Of course there is still a fuse (or 2) that will pop if you forget and connect to a voltage source when configured for current, but at least the volts & ohms scales are pretty much proof against any reasonable voltage.
 
Possible, but usually you're going to be burning bulbs before the coil.
 
sp53 said:
Hi Dale I suppose an easy way to see if your ignition is hot when the key is off would be to either bridge the solenoid or if you have a push button try and start it with the key in the off position. Sp53
Click to expand...

Or... since he doesn't want to risk another meter... use your test light between coil (+) and chassis ground.

Dale, buy several cheap Harbor Freight multimeters. Just keep the probes away from the high-tension circuit and I don't see how you can destroy the cheap digital meter.

The coils you've tried all should have worked without failure. I agree with everyone above who has suggested looking at the car's operating voltage and confirming that the coil is "off" when the ignition is "off".
 
Hello dale,

"if you haven't already done that while powdercoating)"

you had the coil powder coated? were all the burnt coils done or just the first? I believe that will detract from the natural cooling of the coil, which has an aluminium can so will be good at dissipating heat. Powder coating will not help?

Alec
 
Just for the record, the coil was painted red and planted as a "red herring" to see who was watching. Kind of like sticking some poor pale kid from RI next to a street sign in the blazing hot sun of Bayamon, PR.
 
Well now, THAT give away is just gonna get you "Shopped"
again Paul.

Tomorrow, I think I'll powder coat the battery a nice Lucas
green. That will be awesome.

You know, coils now represent just about $40 per hour of
drive time on my car. My insurance runs me another $200
per hour of drive time. It all adds up.

But only $6.00 per year for gasoline, I suppose I should not complain too much. /bcforum/images/%%GRAEMLIN_URL%%/blush.gif

d
 
Dale....
Speaking of gasoline; has that stuff in your garage evaporated into the noon day heat yet?
 
Must be ESP!

I was just this morning shaking both containers to
see if the gasoline had evaporated. It has not.

d
 
dale, Are there as many Hispanic landscapers in your area as in the mainland? I bet they will take that gas of your hands!!!
 
Hispanic landscapers in Puerto Rico?

You can't be serious!! We also have an
immigration problem here on the island.

All these old gringos from the cold states
are moving down here to oogle our bikini babes.
These old gringos have the market for gardeners
and landscapers cornered.

A shame it is. These old gringos will work for
almost nothing. A few shots of rum, some roasted
pork, a few cold Madallas and coupla hours on the
beach.

There oughta be a law!!

d
 
I hear they are buying up all the TR6's on the island also.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I hear they are buying up all the TR6's on the island also. [/QUOTE]

They all have a guy who handles their papers and gets them nice apartments and restored cars. I think he goes by the name of Pedro????
 
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