Warning! Great care should always be taken when working with any electrically charged circuits!

This procedure covers two scenarios, the first being conversion to negative ground while retaining the existing generator to provide power to the battery and the second and probably most popular is the conversion to negative ground in conjunction with installation of a Team CJ Alternator conversion kit. Both conversions are very similar.

Step One:

Disconnect the battery.  (Always disconnect the grounded terminal first).  And if you are going to retain the generator disconnect the wire spade terminals at the generator.

Step Two:

Change the coil wires from negative to positive.  On old coils the terminals are marked SW and CB.  The white wire previously on the SW terminal should now go to the CB terminal and the white/black wire on the CB terminal should now go to the SW terminal and then to the terminal on the side of the distributor case.   Newer coils are marked  (+) and  (-)  and the white wire should now go to the (+) terminal and the white/black wire should now go to the (-) terminal.

Step Three:

At the instrument panel on the center of the dashboard swap the wires on the amp meter.

Step Four:

At the instrument panel on the center of the dashboard swap the wires on the fuel gauge.

Note: Do not swap the wires at the fuel gauge sending unit which is mounted on the fuel tank.

Step Five:

Swap the wires at the explosion proof box in the boot for the connections  to the submerged fuel pump.  The white/purple wire from the fuel pump should be connected to the black connector and the black wire from the fuel pump should be connected to the white/purple connector.

Step Six:

The original Lucas electric motors on the windshield wipers, the radiator cooling fan and the heater fan are field wound and are not polarity sensitive and the wiring should remain undisturbed.  However, if the radiator cooling fan or the heater fan have been upgraded with aftermarket equipment to increase performance then the motor may well be of the permanent magnet type and it is therefore polarity sensitive and the wires to these motors will likely have to be reversed.  No problem, if you don’t reverse the wires the motors will run in the wrong rotation and you will know that you have to reverse the wires.   Also check the polarity requirements of the windshield washer motor which is on top of the windshield washer bottle.

Step Seven:

Reconnect the battery putting the ground cable on the negative post and the positive cable on the positive post.

Step Eight:

For installations retaining the generator, take the wires on the back of the generator and touch  the “B” terminal to the “F” terminal.  This will polarize the generator for a negative ground system.   Then connect  the generator as indicated by  the size of the spade terminals.

Alternator Conversion Kit Installation

First, check that the front engine mounts are new or in good condition. If they are old and have sagged the front portion of the engine will have drooped.  Correct this by installing new, robust engine mounts which will raise the engine to its original position and avoid interference between the alternator and the adjacent sub-frame assembly.  Also with the engine in the proper position, you should be able to remove the old and install the new water pump pulley without having to remove the water pump from the front of the engine.  Further, poor engine mounts may put additional stress on the point where the engine stabilizer bracket is bolted to the bulkhead.  If there is cracking of the bulkhead at this point you will need to effect a small repair/reinforcement.

Second,  if you are installing an Alternator with a built in voltage regulator such as the AC Delco unit supplied with the Team CJ conversion kit, you can connect a new wire from terminal # 1 on the Alternator direct to the brown yellow terminal on the ignition warning light, or pick up the brown/yellow wire from terminal D on the RB310 Regulator or from terminal W on the RB 340 Regulator  and splice and electrically insulate the connection.  When you get through with the wiring, you will find that all the regulator is doing is acting as a common terminal block for 3 white/brown wires (one from the ignition switch, one from the input terminal on the lighting switch and one from the amp meter).

You now have the option to remove these wires from terminal B on the Regulator, splice them together and electrically isolate the connection from the chassis or ground. This done, you can now remove the regulator from the car.

You will find that when you start the engine, the ignition warning light will go out and this is your indication that the Alternator is putting out power to the car systems and the battery.   The amp meter will register on the discharge side only and the meter will indicate the total amps being drawn by the car’s electrical systems.  As the amp meter is no longer connected to the voltage regulator system the charging side of the amp meter will not register under any condition.  This limited use of the amp meter can be helpful for it will indicate if you have left any electrical system turned on when you shut down the engine.    Later E Types with Alternators have replaced the amp meter  with a volt meter which indicates the state of the charge in the battery.

Hope you enjoy all of the benefits of your new negative ground system and especially if you have installed a new Team CJ Alternator conversion kit.

Warning! If you are unclear about any of the above instructions, do not attempt the conversion. Call us on 1 877 PART JAG for clarification, or email us at techsupport@classicjaguar.com before proceeding.