Crown FC 4500 AC DRIVE:
Unit Bucks under light acceleration

Hello,
i have a crown fc4525-50 with an A/C drive motor. this unit has been a long journey so here we are now.
the unit has an issue while driving it will jerk and buck with light acceleration( under 25% on pedal). it will do the bucking and jerking for 3-10 secs then eventually be able to drive out of it. does it both forward and reverse. I have replaced many components at this time and am at a loss. it did code a few times but very rarely for 314.
things i have replaced--access 3 controller, accelerator pedal pot and switch, encoder located inside the drive motor, brake switches, fwd/rev switches.
the 314 code hasn't returned since I replaced the encoder, but it was a very rare/intermittent code to begin with.
I feel as though i am loosing a phase on the drive motor and that is what is causing the bucking/jerking. i'm unsure of how to test for this or show data for it, it is possible the controller was bad out of the box but i doubt it. Any help or foresight would be very appreciated
  • Posted 7 Dec 2022 04:19
  • Discussion started by BigForker52
  • Alaska, United States
Located in the north north

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