murdan

I'm the original owner of a 1991 Cherokee XJ Limited and have given it very good care. A week ago, the driver seat would not adjust properly for the first time. Up/down and tilt adjustments worked fine, but the total seat travel in forward/back was suddenly only 1.75 inches (passenger seat will move 6.5 inches, and at completion of front/back travel, the drive motor shuts off completely). At each limit of driver seat travel, the motor does not shut off. Instead, a loud buzzing noise occurs, as though the teeth on the motor's gear wheel are rubbing on some object. I have removed the driver seat and have separated the motor drive base from the rest of the seat. Visual inspection appears normal. I can see linear gear teeth in the drive track, so obviously the motor is attached to a circular gear with matching teeth. Internet search suggests plastic teeth are commonly used. The drive frame assembly is fabricated using heavy duty press-fit rivets, which I cannot disassemble. The motor assembly is a trio of three motor cylinders attached to a linear housing by six rather small hex head machine screws. The linear housing contains mechanisms connecting each of the three motors to tilt, raise/lower, and front/back drivers. The front/back driver is completely enclosed--I cannot see the motor's drive gear at all.

The internet is absent of any discussion regarding how to remove the trio of motors, which appear to share a common case, like three hot dogs side to side. Before I remove the six machine screws that mount my "hot dogs" to the linear housing, I'd like to have an idea about where I might be going with this problem. The passenger seat works fine, so the passenger seat motor is and "installed spare" that I could swap with the driver's seat motor if necessary (for example, if the driver's seat motor's gear wheel is defective).

This is a good Jeep and has a lot of life left in it. I can live with a passenger seat that is not adjustable, but wife and I need an adjustable driver's seat!

Any suggestions from someone who has faced an issue like this? Are replacement motor trios available on the open market?

Many thanks!