Is anybody else a fan of these wonderful vintage accessories?
I have fitted them to all my Sevens and latterly run them with electronic ignition. I have always found them fantastic.
But I have one question. They seem to have a very unusual output connection arrangement, which I have been puzzling about.
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.
04-04-2022, 07:29 PM (This post was last modified: 05-04-2022, 12:52 AM by Tony Griffiths.)
How odd, I tried electronic ignition on my 1929 Chummy with a Runbaken coil and it ran like a limping camel. Swapping to an old conventional coil cured it. For those who don't know what a Runbaken looks like, here's a pair.
EDIT: The car ran fine on the Runbaken before - there was no need to fit electronic ignition, which has now been removed.
Commercial Motor September 1941
Oil Insulation in Heavy-duty Ignition Coil
A new Runbaken device, named the Oilcoil, which constitutes an adaptation of a principle Employed in Large Transformers for some years the gains in engine performance and petrol economy that can ensue from the use of widegap sparking plugs have been becoming more widely realized, The increased electrical pressure demanded has resulted in the development of high duty ignition equipment, and a recent addition to the range of proprietary components of this description is the Runbaken " Oilcoil."
As may be deduced from the name, the salient feature of this device is that oil is used as an insulator. The special interest of this practice lies in the fact that it is a new application of a principle that is universally employed in industrial electricity generation—or rather distribution. Extremely high voltages are commonly used for the transmission of electricity, notably by the grid system, and this practice entails the, use of transformers which are oil insulated. Virtually, no other form of insulation would be practicable, for not only is transformer oil a first-class non-conductor but also it is fluid and can circulate, thereby disposing of the heat which would otherwise reach an undesirable magnitude.
The oil-insulated ignition coil benefits in comparable manner. In the case of the " Oilcoil,:' made by Messrs. Runbaken Electrical Products, 71-73a, Oxford Road, Manchester, 1. the HT output is stepped up to 28,000 - 30,000 volts, compared with the 15,000 – 18,000 volts of an ordinary coil, and the consequence is a more intense -spark across a 0.04-in, sparking-plug gap instead of a 0-02-in, gap.
Claimed to be practically indestructible, this Runbaken device is guaranteed for two years, is not harmed if the ignition circuit be accidentally left switched on, has a low current consumption and affords good starting. The price of both the 6-volt and the 12-volt models is £2 14s.
Beware that transformer oil can have "nasty" ingredients
I have been running my Box Saloon on a Runbaken coil since I bought it in 1970 and iy has never (touch wood and whistle) missed a beat. Quite a feat...
I fitted a very second-hand one to my Ruby when it went back on the road in 1975 and it has given faultless service ever since. Fitting electronic ignition, probably one of the best mods. I’ve employed over the years, made no difference. The spare Oilcoil I acquired at about the same time as I got the original is still sitting on the shelf. They definitely get my vote!
Alastair
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?"
05-04-2022, 01:05 AM (This post was last modified: 05-04-2022, 01:19 AM by A G Wood.)
(04-04-2022, 05:24 PM)Martin Baker Wrote: 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) ?
(05-04-2022, 01:02 AM)Tony Griffiths Wrote: 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?"
I cant find it at the moment but there was a celebrated case in the US a little while ago where a local authority had, for decades, been using used transformer oil donated by the local electricity department -it was customary practice to change the oil periodically- as a zero-cost spray on rural 'dirt' roads to reduce dust. When the inevitable happened, the authority then had to scrape off and safely dispose of the top 300mm/12 inches of many miles of road surface.
Its also not unknown to find PCB oils in older fluorescent light ballasts.
