E-unit Replacement

I have a GP20 Diesel that the e-unit is buzzing louder that our kitchen blender does on high speed. I have bought a new electric e-unit, but cannot figure out how to wire it back into the Diesel. Both the new e-unit and the Diesel have 4 wires each. If I wire it up like I think it should go the motor sits at a stall, it sounds like the armiture is trying to turn in both directions at once. It is not making any scent to me. Can anyone help.

I

The noise is normal for the GP20’s… almost empty sheet metal chassis, & slightly louder E-units in that time period.

The electronic e-units are for DC motors typically(unless you were able to source a ACRU-E) and won’t work with a series wound universal motor unless the field & brushes are isolated, and you run it on reversing the DC polarity. Current draw is then a concern, they weren’t meant to power more than two can motors.

Rob