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MG Midget and Sprite Technical - new distributor wiring

just a quick one, i;m fitting my new simon bbs dizzy with electronic ignition. no instructions and 2 wires, one red one blue. where do these go? thanks in advance.
paul sewell

Try this!

Kit Installation

a) Distributor fitted to the engine.

The Simon BBC module kit can be fitted to the distributor while the distributor is still installed in the engine of most cars.

The design of the module ensures that after fitting the engine will start with the same static ignition setting as near as possible to the same as with the contact point specification.

We recommend final ignition timing to set dynamic using a strobe.

The mechanical and vacuum settings of the standard distributor remain un-affected.

b) Distributor removed from the engine.

The Simon BBC kit can be fitted to the distributor on the bench the same way as if it was installed in the engine except that the firing position for initial start up can be checked with the engine at TDC by observing that the black trigger ring has individual magnets inserted in the plastic and one of these need to be aligned with the centre pickup of the red module to find the static firing position that corresponds with the rotor arm in No1 position. Turn the distributor to achieve this before the distributor is clamped in position.

We recommend final ignition timing to be set dynamically using a strobe.

If the kit is obstructed by a pin or lug on the base plate, we advise removing this obstruction (this can be done without damaging your current distributor) we find that this pin/lug is present with blue points

If you can't get the ignition to work once installed, try these suggestions:

Check the wiring:

1. The Simon BBC module is designed for 12V negative ground applications only.

2. Condenser and wires from distributor should not be installed in vehicle once the kit has been fitted. Connect any other wires to the coil in their original positions.

3. Check the coil resistance to ensure that your coil has a resistance of more than 1.5 ohms and remove any ballast resistor present in your vehicle for this measurement.
One of our standard points type coils is recommended.
If you are unsure about the coil that is fitted to your vehicle the coil should have a minimum primary resisitance 1.5 Ohms.
The Simonbbc ignition red wire connects to positive ( + or 15 on Bosch coil).
The black wire connects to negative ( ve or 1 on Bosch coil).
To measure primary resistance: Label and remove all wires to coil. Using a digital multimeter in the 200 Ω mode, measure between coils + and - terminals.
Allow a few seconds for the reading to settle. For best performance, the coil should have a minimum of 7,000 Ohms secondary resistance (measured from the coil +ve or ve terminal to center high tension terminal, in the 20K Ω mode of the Ohmmeter)

4. Connect the Black wire to the coil negative ( -ve or 1) terminal. In the case of positive earth vehicles converted to negative earth ( eg Lucas 25D ) establish the feed wire ( live with ignition ON ) and the opposite terminal is the earth or ve.
5. Connect the Red wire to the coil positive ( +ve or 15) terminal. In the case of positive earth vehicles converted to negative earth ( eg Lucas 25D ) establish the feed wire ( live with ignition ON ) ie +ve.
6. For testing purposes, no other wires should be attached to the coil terminals, except for the center high-tension lead to the distributor cap.


Timing:
You can set the timing dynamic with a strobe light with points ( engine running ) and with electronic system you can do the same.
You can set the timing approx as before static, and you will need a strobe light ie + and ve to strobe and sensor lead to No1 plug lead to set the timing dynamic and then adjust to max @ 3500 rpm say 24 degree (depends on the vehicle and engine).
The electronic ignition module is mounted as near as possible to the same position as the points were, but in some cases the distributor will possibly have to be turned +/- 10 degrees from where it was with points. Setting the timing is recommended once you have fitted one of our electronic kits. Setting by dynamic is the best and most accurate way to adjust the timing.

Battery voltage to coil:
With ignition switch ON, engine not running, check voltage at coil + terminal. The voltmeter should read somewhere around +11 to +14 volts. If voltage is too low or theres no reading, the battery terminal or ground connection may be corroded and need cleaning or the battery may need charging. Some vehicles have a resistor wire running from the ignition switch to the coil +ve terminal. This resistor wire drops the voltage below 9 volts so you may need to run a non-resistor wire from the ignition switch to the coil + terminal or run a +12V wire directly from the ignition switch to the red wire of the Simonbbc ignition module. Make sure that the ignition switch terminal to which you connect this wire has power only when the ignition switch is in the ON position. Or you can, for temporary testing purposes only, run a wire directly from the battery's + terminal to the coil + terminal, the Simonbbc ignition red wire to the coil + terminal and the black wire to the coil -ve terminal. Do not leave the wire from the battery connected to the coil + terminal for more than a minute or so without the engine running.

Jump-starting the vehicle:
Simonbbc recommend using caution when jump-starting the vehicle fitted with our electronic kit. Connect the battery's + terminal to the other vehicle's battery + terminal. Connect the negative (black) part of the jumper cable to engine ground points, such as a bolt on the engine block, on both vehicles.
Do not turn the ignition switch to the ON position while the vehicle at the other end of the jumper cables is running. Charge your vehicle battery with the other vehicle or with a battery charger and then remove the jumper cables or charger before turning on the ignition switch and starting your vehicle. If the ignition switch is in the ON position while both vehicles are running, the electrical surge resulting from both vehicles' charging systems being connected together with jumper cables could be enough to destroy the ignition module and/or other any electronic components.

Gap between the black trigger and the ignition module:
If you need to increase the air gap slightly, hold ignition base plate away from distributor shaft while tightening set screw and/or loosen the two screws and retighten screws while lightly prying ignition module away from magnet sleeve. Do not over-torque the screws. The black magnet sleeve should not rub against red ignition module, but exact gap is not critical. It may be necessary to gently pry red ignition module away from black magnet sleeve to keep them from rubbing together.

Vehicle System Voltage:
If the charging system voltage, measured at the coils positive terminal, is more than 14.2 volts at 2,500+ RPM, the voltage regulator may need replacing. Too much voltage can damage the ignition module and other electronic components. A maximum charging system voltage of 13.5 volts is adequate
Warning:
Reversing the red and black ignition wires will destroy the ignition module and void the warranty. Returned modules will be examined internally to establish the components damaged to identify if this has been done.
Using a coil with too little primary resistance can cause the ignition module to overheat and fail, thus voiding the warranty. Returned modules will be examined internally to establish the exact damage to identify if this has been done.

d cusworth

thanks very much for that, finished and just been out for a blat, WOW !!! what a difference, would recomment it as a good value for money upgrade, cheers, Paul.
paul sewell

This thread was discussed on 03/07/2010

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