Runbaken Oil Coils

[Hugh Barnes]

Google suggests "Polychlorinated Biphenyls" and suggests this as a resource ..

https://safety.networkrail.co.uk/wp-cont...e-Note.pdf

[Ivor Hawkins]

Crikey, what with a lifetime of handling old engine oil, cellulose paints and thinners, asbestos brake dust flying around and now Runbaken coils, it’s a wonder I’m still here!

[Nick Lettington]

What is PCB?  To me that means Printed Circuit Board.

https://en.m.wikipedia.org/wiki/Polychlo...d_biphenyl

We dealt with this regularly in railway sidings... I wanted an oil coil for my special until it dawned on me what the oil was.

Other than risking birth defects in your progeny and cancer, I can't really see any drawbacks.

[Tony Griffiths]

There is a step at the bottom of the thread for the acorn, which would appear to prevent the ignition cable from actually making contact with the coil output. Is this intentional? Is it an air gap? In which case to what purpose? I have always got around this by dropping a small nut in the void.

Anybody got any bright suggestions?

Any chance that they originally came with a unique Runbaken nut (like the Lucas 422792 one the SA12  'red' sports coils used) which has been lost in the mists of time?
I've handled second hand Runbaken coils back in the day but being young and foolish I never paid too much attention to design details.
Also regarding the void, what would be wrong with an insulated spacer on top of the split washer to take up the slack (rather than the other way round like you've done) ?

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A post from another forum about the very dangerous PCB oils inside these coils: 
"I hate to be negative but while these coils are very quaint, PCB oils are so thoroughly nasty they have been banned for over 30 years. Contact with PCB's offers a generous selection of serious health hazards including cancer. PCB oils do not burn like other oils, which is great for use in coils and transformers but challenging for safe disposal. PCB's do not readily break down in the environment and remain potentially deadly for generations. Your local Environmental Health people can help deal with these safely and the service is free.If you can be certain your Runbaken coil will never get broken or leak or get opened up it is probably perfectly safe for you and your children and your grandchildren. But is it really worth the risk?"

It's also not unknown to find PCB oils in older fluorescent light ballasts.

When I built my current garage in 1979 the cheapest fluorescent light fittings I could find were made in East Germany - from memory about £2 each for a 6-foot unit. I took the last surviving one to the tip just a few months ago. One wonders.....

[Martin Baker]

I was thinking the same as AG Wood, that there was a special Runbaken nut. Love to see a picture, if anybody finds one.

[Hugh Barnes]

Seemingly nothing special here?

   

[Martin Baker]

Look down the screw hole and you should see what I mean. A shoulder preventing the lead disc making contact.

[Hugh Barnes]

Ah, I see.. I will look again...

[andrew34ruby]

This might be of interest:

Commercial Motor September 1941
Oil Insulation in Heavy-duty Ignition Coil
A new Runbaken device, named the Oilcoil, which constitutes an ....

I can't imagine that the oil is the insulation, surely it is just for cooling, conducting the heat away from the varnish insulated copper windings.

Does anyone know why they used this dangerous oil? Presumably the common oil-filled coils of the fifties through to nineties were using a different oil?

[Bob Culver]

A year or two ago at a public car show one of the 12v Bradfords had been fitted with a 6v coil. The igniton had been left on and whilst several curious were examining the unusual motor the coil exploded...... It definitely had oil in it!
I dont know when PCBs arrived, probably in the 1950s along with many other nasties. Presumably transformers were oil cooled before PCBs. And presumably when used the PCB concentartion was more like 100%.

With a normal mixture very little is required to ignite. I have a handbook for a Pratt and Whitney Double Wasp and the plug gap is just .012".  Big gaps and fancy voltages are requird for weak mixes as moderns and as erratically occur at idle and starting. From extensive everyday experience with my RP I suspect plug gap influences effective advance.