Ignition coil with black oily substance

[Bart911Man]

Here's the thing,

My RPM gauge started to read funny the last few days.
Yesterday the P machine started very badly, but once
up and running it ran like allways ... groovey.
This evening it doesn' start at all, tested plug ... no spark.
Tested coil, primary 0.6ohm secondary 683ohm.
BUT there is black stuff coming out of one of the primary leads it already stained on the distributor cap,
when I shake it no sound is heared...

Is the coil the source of my ignition problems? even with the good resistance measurements or do I replace it preventivaly and look farther for my starting problems?

I know if I replace the coil tomorrow I'll find out right away but weather is great and I want my baby back as soon as possible... you understand? you input may give me extra days of pure pleasure.

Thank you,
Bart '80SC Targa

[Early_S_Man]

Most likely, yes ... even though the resistance readings are normal! The fact that the coil is leaking is a sign it is, or has been overheating in the recent past ... most likely from a breakdown in the secondary winding.

You are aware that the only coil that should be used is a Bosch 0.221.121.001 or 0.221.121.006, right? The '001' is the 'universal' CDI replacement, and the '006' is the late SC CDI coil with closely-spaced 'A' & 'B' terminals.

Hopefully, your CDI-unit didn't get fried by high Voltage fed back into it from the internal arcing!

[Bart911Man]

Thanks for confirming this.

Here's another Q:
I have now the 0 221 121 001 coil, would you recommend replacing it with the same type or is there advantige in upgrading to a 006 type of coil?
My p-car is a US '80SC Targa.

The CDI-unit is whisteling quit fine, so i think (whishfull) it did't died on my coil problem.

Thank you,
Bart

[Early_S_Man]

Bart,

I can't think of any reason to 'upgrade' to the later coil ... the specs are the same, and there is no difference in output Voltage, based on tests I have done with a spare coil. There is a late SC dust/watershield boot that fits it ... but I have never seen the '006' coil for sale in any catalog. A dealer-only item, I suspect, and I'm sure you don't want to pay a dealer price for no difference in performance!

[tmctguer]

i had a similar problem only 6 months after replacing my original black bosch coil with a new silver coil (from brazil??). one day my car died on the freeway, and after a $100+ tow truck ride home, i found oil had been leaking out of the coil. i put the original back on, and she fired right up. all traditional coil tests showed the coil to be OK.

i got a refund from the vendor for the defective coil.

[Bart911Man]

Went past my mecanic last evening, the good guy spare me a 2nd hand coil (he didn't know if it was a good one), to test.

Nothing

Did the standard coil measurements, all within specs.
The odd thing is the weight of the spare coil is exactly the same as my old one. So, could be my mecanic just had a bad one on the shelf.

What warryes me the most is that I read a document stating I should measure 4-5 VDC on the primary leads. (from the ignition troubleshooting guide on the Pelican tech articles).
With the coil connected I have 0.0VDC with the A lead disconnected I have 0.12VDC.
Have I fried my box?

Thank you,
Bart.

[Bart911Man]

Picked up a rebuilt CDI and a 2nd hand coil from the local P-club.
Started first cranck. 200$ in stead of 1000$. This realy was my lucky day!

Thanks for the advise guys.

The way you analise these things (from about 10K miles distance)
is frightning

Bart.