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MG MGB GT V8 Factory Originals Technical - Distributer with balsat resister

Hi All
I have fitted a distributer with a balast resister on the side, where do the connectors on the resister go to, i am assuming that they go to the coil, if so which to which?

Thanks
Graham
Graham lavis

Graham,

Whether or not you need a ballast resistor is determined by the coil, not the distributor. You'll need to check your coil to see if it needs one. If it doesn't say on the coil and you can't get manufacturer's data, measure the resistance of the primary side of the coil. If it's over 3 ohms, you don't need one. If it's 1 1/2 ohms, you do.

If you need it, disconnect the power lead to the plus terminal on the coil and connect it to one side of the resister. Connect the other side of the resistor to the plus terminal of the coil. It doesn't matter which side of the resistor is which.

If you have trouble starting the car with the ballast, you will need to add a bypass wire to the coil. To do this, run a wire from the "ballast bypass" terminal on the starter solenoid (if it has one) to the plus terminal of the coil (along with the wire from the ballast).
Dan Masters

Graham,

Are you sure it is a ballast resistor and not the amplifier for an electronic distributor? Is the distributor from a Range Rover?

Geoff
Geoff King

Graham,

if it is a 9BR resitor from a SD1, You will have to do the connections as follows:

Have a look upon the body of the resitor and spot out SW+ stamped on it.
This connector takes the white/black wire to the tach.
The socket beneath this will have to be connected to the igniton switch with the white wire.
There is third socket that has to be connected to the white/yellow wire giving 12 Volt from the turning starter motor.

on the other side of the resitor, there are three sockets too.
Starting with the one just oposite the SW+ position,
this socket has to be connected to the white/blach wires from the distributer and the (-) terminal of the coil.
The socket just beside this one is connected to the Lucas Opus distributer with a red/black wire and finally the white /green one on the last free socked is connected to the (+) terminal of the coil.

The heat shild of the resitor must have a good connection to the vehecles groud too.

This is the setting Rover used on their SD1 cars and it also works for me in my GT V8 conversion since the early 80's.

Check out that you use the right coil with this type of resitor. It must be a Lucas 22 C 12 (electronic) for the use with the 35 DE8 Opus distributer.

Be prepared for things to come and have a look upon the site of Newtronics (Piranhia before), as they make a usefull electronic for this distributer at a reasonable price.
Normaly there is nothing wrong with the Opus, but failiures due to heat can occure and spares for the OEM 35 DE8 are very expensive and do not last very long under the bonnet of a MG B.

Ralph
R.S. Ralph Siebenhaar

Graham,

Can you tell us the type of distributor you have?

The Lucas 'OPUS' 35DE8 had a separate ballast resistor mounted away from the distributor. I doubt if you have fitted one of these.
The 35DM8 replaced the 35DE8. It had a separate ignition amplifier mounted underneath the coil. It doesn’t have a ballast and it doesn’t sound like you have one of these either.
The 35DLM8 replaced the 35DM8. It is similar to the 35DM8 but the ignition module is attached to the side of the distributor. You possibly have one of these - but it isn’t a ballast resistor on the side of the distributor.
Early versions of the DLM8 had a 2-pin amplifier module later ones were 3-pin.

Geoff
Geoff King

I will get the details off the dizzy as soon as possible and post the details.

Thanks
Graham
Graham Lavis


Here's just a little more information along the same lines as Geoff's post... (maybe it'll help you i.d. the distributor).

http://www.britishv8.org/Articles/Selecting-a-Rover-Distributor.htm


Curtis

Hi
I got a friend to look at the distributer for me as i am not with the car at the moment.

Numbers on the dizzy...86198A the (1) might be a 7
also 2664.

he says it might be a bosch? it is an amplifer on the side.

Any idea's?

Thanks
Graham
GLG Lavis

This thread was discussed between 18/07/2006 and 21/07/2006

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