Ignition Coil Cleaning

[ecb056]

After discussion with another member regarding the coolant tank (aka Header Tank) catastrophic failure, it was recommended to “clean” the coil. I read thru the LEC links and WikiLEC and am not sure what exactly to clean on the ignition coil.

I labeled the WikiLEC picture with the components (of one coil), and had several questions.
1. If I do not clean the coil until I start noticing miss firing, is the potential damage reversible by cleaning or will a new coil be the only remedy?
2. Would the miss firing occur at a specific RPM range due to damage caused by the leaking coolant tank?
3. I assume the “coil” is under the black plastic and should be sprayed with Electric Parts Cleaner (CRC Lectra-Motive – contains Tetrachloroethylene – chlorinated solvent), is this correct – any suggestions/recommendations?
4. How do I access the coil – are those torx screws at (A) and (B) and do both/either need to be removed?
5. Any experience with electric parts cleaners compatibility with the plastic case the coils is mounted underneath? The “brake cleaner” is a different chemical composition consisting of toluene, methanol, acetone – all non-chlorinated solvents)?
6. Does the ignition wire post (C) need to be removed and cleaned – what exactly would there be to clean – I assume it is just a metal post and how would it be removed – I assume it is a molded piece?
7. Do the electrical terminals (D), (E), (F) need to be cleaned?
8. What other issues, steps or concerns should be addressed?

[Brit-Car-Nut]

Since your picture didn't make it to the post, I am not sure about what parts you are referring to by your references. I am looking at http://wikilec.9600.org/index.php/Ignition_Coil

The coil IS the black plastic. There are TWO. They attached to a bottom plate. There are 3 harness connections going to the coils: 2 for the coils and the one in the centre for the botom plate. ALL of the connections need to be cleaned and dried including removing the coils from the bottom plate and cleaning those connections. The coils are held down by normal hex-head screws. The plug wire posts are part of te coil and don't come apart.

Everything that can be disassembled should be cleaned (dirt, grime and antifreeze) and dried. Most techs speed the drying process by using brake clean or electro cleaner but alcohol will work too albeit slower. Compressed air after spraying will hasten the drying process. The brake clean etal displaces the water/antifreeze and then air dries in a relatively short time. The plug wire ends shpould also be cleaned and dried.

Failure to dry and clean will allow corrosion to start and will shorten the remaining life of the parts. Coils are relatively inexpensive but the bottom plate is not so cheap.

[tigerdog]

If the car has been run or driven with misfire after a coolant overflow, also check very closely for a carbon trail on the surface of the coil between the ignition lead towers and any possible earth ground location. Though I've never seen it in an Elan, even the tiniest surface trace will give the the high-voltage electricity somewhere to go besides the plug lead and you'll get misfire. Could be all the time or only under a load.