Thread: Question about rewiring the coil

[b]<span style="color:green">the resistor is to stop the coil from burning out.....
the condenser is there to stop the points burning out....

it needs a resistor to lower the voltage down to around 7 or 9 volts to stop it from overheating and burning out......


whilst cranking the engine the ignition circuit will by-pass the resistor to give full voltage and stronger spark to assist in the initial starting up of the engine....
once the key is in the 'on' position....the feed to the coil will run through the resistor....





now back to your query......turn on your ignition and check what voltage you have at the coil +ve terminal (with the coil disconnected)
if you have a full 12-13.8 volts you should be running a resistor with your coil..... or get a 12volt coil(one that does not require a resistor)

if you have 7-9 volts there is already a resistor fitted....


oh....by the way...a resistor is usually a ceramic thingy about 5-6cm long and white in colour....
(if you dont know what you are looking for its hard to know whether removed one or not....)</span>

Ok, thanks. It is a bit hard to check voltage as most of the wiring is pulled out at the moment. I will get a resistor then check voltage once it is all up and running. I know what it looks like and I did not see one but then again I was not looking at the time.

It is a bit of a worry when the auto electrician does not know what he is talking about as he said the reisitor was only to protect the points? Must remember not to get any work done there.

Did the original Rangies have a 12v coil? I did not see any mention in the manual or the wiring diagrams for a resistor?

A 1977 Range Rover has areisitor wire to the coil from the ignition switch.
The giveaway is that there are two wires to teh positive of the coil, one comes from the starter solonoid, and is only active on cranking (12v) and the other goes direct (8v).
Justy check the wires with a multimeter, to see in case someone in the deep dark past has fiddled. So if all is correct you do NOT need a resistor.
Make sure you fit an 8 volt or resistor coil.
Regards Philip A

Believe me...someone has fiddled! Which is why I am rewiring, and that means replacing every wire, I don't trust any of them. On just one wire which ran from the ignition to the fuel pump there were 9 seperate inline joins!!! 8O

Well mate, what you do is run one wire from the small terminal on the starter solonoid. This gives 12 volts, or whatever volts are left over in the battery with the starter cranking. This is only active when the starter is turning.

You run one wire from the "on" postion of the ignition and you put a ceramic resistor on this to drop the volts to 8 or so.
You fit a resistor coil, and make sure it is a conventional coil NOT an electronic coil. Ask me how I know how much a new Luminition is.

So when you are starting the coil get extra juice to compensate for the volts taken by the starter, giving better spark, but as soon as she catches you get 8 volts which ensures the coil does not overheat.
Regard s Philip A

Range Rovers have 9V coils and not 12v.
Common mistake. Will run on 12v but burn't out points or coils quickly , and i mean quickly.
Useally the wire to the coil is a resitor or there is a separate resitor on the bulkhead

Thanks all, I bought a resistor and installed it today.

G'day Walker [img]style_emoticons/<#EMO_DIR#>/smile.gif[/img]
The easiest way to to check a coil is that on most Australian specced vehicles the coil is stamped on the base, "Use with a Resistor" on Bosch "GT" series coils they are sold branded as GT-40(STD) or GT-40R (RESISTOR), most 60's,70's 80's Lucas coils were also stamped on the base [img]style_emoticons/<#EMO_DIR#>/smile.gif[/img]
cheers.