19 replies to this topic

[rough1]

i know it's a daft one but, where does the white resistive wire go, if it fits on the coil which terminal will it go on....thanks

[oliver122]

i traced mine up to the loom where it go's through the bulk head and it joined to another 3 white wires , i cut mine out as it set alight and melted the insulation on some of my other wires. The 3 white wires are ignition switched power supplies, so anything that operates with the ignition switched on will come from these.

Edited by oliver122, 23 November 2011 - 09:25 PM.

[firefox]

Do you mean the pink and white ballast resisted wire if it is pink and white it goes to the positive terminal on the coil

Edited by firefox, 23 November 2011 - 10:38 PM.

[dklawson]

As Firefox said, pink/white is the color of the resistive wire.
In Lucas wiring schemes, the white wires are unfused wires that are live when the ignition switch is turned on. White wires are full 12V, non-resistive wires.

[Timty]

Could someone explain what the pink and white resistive wire is for and what makes it resistive? (if that makes sense) and why did they not use a normal wire and a resister? sorry if it's a daft question!.
Tim.

[firefox]

As Firefox said, pink/white is the color of the resistive wire.
In Lucas wiring schemes, the white wires are unfused wires that are live when the ignition switch is turned on. White wires are full 12V, non-resistive wires.

I am not 100% but i think depending on the type and year of car the ballast resited wire is knocked down to 9V that is why if you put a 12 coil on you have to run a 12 volt new cable from the fuse box to the live terminal

[Guess-Works.com]

Basically the theory behind the ballast system is, the coil is designed to work at a lower voltage 9v or there abouts, the resistive wire is made of a material which is not a pure conductor like copper, therefore lowers the voltage... This does not change the running of the vehicle, however it does mean that on starting, the coil can be given a full 12v feed from the starter solenoid ( Yellow wire ), therefore 'overloading' the coil to produce an enhanced spark. This does not damage the coil for the short period of time, but assists starting. If you were to put a permanent 12v feed to the coil, it would eventually overload and blow.

[cooperrodeo]

Coated? How does coating alter the resistance?

[Timty]

So do ballasted coils work at 9v all the time? (except on start up) and do non ballasted coils therfore work at 12v all the time?

[cooperrodeo]

Coated? How does coating alter the resistance?

A Copper wire coated in a different type of metal, has a different resistances.

That does not change the resistance of the copper wire.

[dklawson]

John's explanation on the pink wire is correct, it is an alloy of copper, not a coating.

I also want to point this out again as I do in EVERY ballast ignition thread. There is NO voltage drop across the pink wire until current is flowing. What does this mean? It means that there must be an earth connection on coil (-) (either the points are closed or the ignition module is "conducting").

If the points are open and you put a meter between earth and coil (+) (where the pink wire connects) you will find full battery voltage (i.e. 12V). Close the points and repeat the measurement and you will measure between 6V to 9V. Current MUST be flowing through a resistive element for that element to experience a voltage drop.

[dklawson]

If you don't need the added starting boost provided by a ballast ignition system then yes... you can replace the pink wire and switch to a standard, non-ballast coil.

However, the ballast ignition system is not that complicated and it does provide a starting benefit. If you already have a ballast ignition system there is a less expensive work-around than converting the coil type. Visit your local auto parts store and ask them for an external ballast resistor (1.2 to 1.5 Ohm) along with its mounting bracket, buy some crimp terminals, and a length of white 16 AWG (1.3 to 1.6 mm squared) hook up wire.

Remove the pink wire from the ignition switch and from the coil (+) terminal. Run the new white wire from the ignition switch to the engine compartment. Connect the engine compartment end of the white wire to the new ballast resistor. Run a short white wire from the other side of the ballast resistor to the coil (+) terminal. Mount the resistor somewhere out of the way where nothing will touch its exposed terminals. You have now replaced the resistance wire with a ballast resistor.

Once you do this, the ballast ignition system will function as before but little to no heat will be generated inside the loom. The ballast resistor and wires will cost less than a new coil and you have retained the easy starting function.

[dklawson]

As I post on almost every ignition related thread, coils seldom wear out. Yes, it happens, but it is not common. It is certainly no more common for a ballast coil to fail than a standard coil.

BMC/BL/Rover used the ballast ignition system on cars (prior to electronic ignition) to help cars start easier. Remove it if you want it is a personal choice.

[dklawson]

My Mini is a Swiss Mini from 1964 and the Mini stopped being imported here sometime prior to 1970. However, the ballast ignition system did make it over here on all the BL vehicles that were imported through the 1970s. That includes MGBs, Midgets, and all the TRs. You can extend that to a few other marques as well.

Of note is that many of the TR models did not use the pink wire but had the external ballast resistor I mentioned above. My Spitfire for example has the external ballast resistor. The Spitfire is much easier to start in cold weather than our GT6 which has a standard ignition system.

I would not consider a ballast ignition system to be a fashion statement. BL was not known for putting things on a car that they could do without. Nor would I consider my support for the ballast ignition system a "love affair". I simply look at the price of the components (about $45 for a Bosch Blue coil) vs about $10 for a ballast resistor... and choose the least expensive "repair" that will keep the engine running. I don't understand why anyone would recommend throwing away or replacing a functional coil of any type.

[cooperrodeo]

It was a fashion thing doug, everyone else was fitting 'em so rover did as well. Only they 'bodged' it with that ******* stupid wire.

It was not a fashion thing at all. I well recall the difficulties cars had in the 1960s starting on cold damp mornings, particularly with the dizzy exposed at the front on Minis and 1100s. Triumph Spitfires migrated from a separate resistor to the resistance wire as my 1500 has the wire. It has never given any trouble in the 32 years I have had the car.

Nowadays there is less of a problem with starting if electronic ignition is fitted.