Generator for the MB/GPW, CJ2A and CJ3A

There is a big differense between the generator for the wartime jeep and the civilian jeep. On the MB/GPW generator the field coils are connected to the generator house inside the generator. The other end of the field coils are connected to the screw (marked F) on the outside of the generator house. This is the positive end of the field.
If you open a generator for a CJ-Jeep you will find the inner end of the field coils connected to the pos. brushes and the screw on the outside (marked F) is a ground connection. This is important for the work of the current regulator.

In this old MB generator I have fixed the collector in a lathe and changed the ball bearing at the drive end. Sealed ball bearings are perfect to use.
The bushing in the rear end is also changed and of course I use a new set of brushes. The inner cables must also be checked.
Today the brushes you see in the picture to the right are hard to find items. Original Ford brushes for the generator and starting motor. If you take a good look you can see a little stamped "F" on the conn. tag on the generator brushes.

If you want to check a MB/GPW generator, this is a fairly simple test.
Connect the "F" terminal to the "Arm" terminal with a piece of cable. Then connect the minus terminal on a 6V battery to the generator body (Ground) and the positive terminal to the "Arm" screw on the generator. If everything is OK the generator will now run as an electric motor.
If you want to do the same test with a CJ generator you must connect the "F" terminal to ground. Then battery + to "Arm" and battery - to ground (body).

HOME

Copyright: Lars Svensson.