'new' control box

Hi all, when I finally got my '36 2.5 sedan back on the road about 10 years ago, the original RJF-50 electrical controls box was not repairable, so I fitted a new replacement without enquiring too much into its origins - I was so delighted to be told they were available! Since then I have had a number of electrical issues with the car, largely around the ignition system. I see that these replacement boxes are not highly regarded by the manufacturers of a solid-state substitute but I would be interested if anyone has had practical experience with them?
Chris Lovell-Smith

I guess the manufacturers of solid state ignition systems would claim their superiority. In fact the original coil ignition system is very reliable although it can be let down by modern components. For example some modern black rotor arms are made from a composite that includes carbon and when they warm up they become conductive and cause misfiring. Stick with original Lucas rotor arms or if you must, buy a modern red one.

I will admit that the original Lucas parts can cause problems too. If you have a distributor with a Bakelite points platform it’s not unknown for the internal earth connection between the points and the metal distributor body to fail.

This failure allowed a very simple roadside repair (something that electronic systems are less amenable to) with the addition of a small piece of wire.


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Peter’s remarks on rotors have been experienced by me as well. In addition, I found an old original unused distributor cap which looked beautiful having corrosion on the high tension feed screw which caused intermittent ignition failure when warm. Sitting decades on a shelf is not always beneficial. And I’ve seen tracking inside replacement caps but the dark brown ones of the last ten years seem good.

By the way, the quality control/functionality of replacement parts also is problematic even on old Fords like my 1930 Model A. Even the replacements with Ford logo on them can have problems. The market is just so small that extra care in part reproduction is not always financially viable.

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I don’t understand, Chris. Is your problem with the voltage regulator or the ignition system?

Regulator problems can often be traced to dirty wire contacts.
I took my regulator off and thoroughly cleaned the back side with pool & toilet cleaner, then rinsed with alcohol. The brass parts finished up all nice and shiny.
Also cleaned the contact points in the regulator and cutout.

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Rob, the original box was said to have burnt out coils - I didn’t pursue that further. The later (new) box is from India, I believe, although it was not marked as such. The most recent issue is a short circuit which cause melted insulation and smoke in wires in the ignition and ammeter circuits as well as loss of engine functions. Unfortunately when smoke appeared I disconnected wires more or less at random - somehow got the car going and got home, but now can’t find the fault. My question was whether anyone had experience of the foreign make boxes, to which I can now add “any experience of the UK-made solid state replacements”?

Smoke and melted insulation in wires in the ignition and ammeter circuits can be from old, frayed wires where insulation has failed. I’ve seen two smoking dashes in Mark V cars from such.