Figured I would post this here, after tinkering over the last couple days trying to figure out a way to rebuild my old rear heater motor that is quite corroded, and brush holder destroyed, I figured I would try to find a modern replacement alternative as a stopgap measure until suitable OEM parts became available (or a bit more affordable). After taking some measurements I wound up with the following small electric gear reduction motor from amazon: Amazon.com - https://www.amazon.com/gp/product/B072R5G5GR/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&th=1
After playing around with mounting options I decided to simply mount the new motor inside the old motor housing. The magnets still being glued to the housing meant that the motor was quite firmly held in place, with about a 1mm gap around the new motor, not bad. The tabs that used to secure the cap and brush housing on the motor work excellent to center the new motor, new wiring was soldered onto the new motor as well and routed out the top of the housing.
The fan fits the existing shaft on the motor without modification, the new motor has a "D" shaft instead of the original round shaft but the grub screw seats on the new shaft without issue. I added rubberized and adhesive backed pipe insulation foam (two pieces back to back making a thicker piece with no exposed adhesive) and it centers the motor well. A zip tie was added for wire routing away from the fan.
Testing the security of the motor:
Install is no different than the OEM unit, I used a section of the old wiring and bullet connector for visual originality.
Its summer and I have not tested the output of the unit, I also have no working OEM motor to compare it to. If I had to do it again I would have found a 750-1000 rpm motor instead. Hope this helps someone get their rear heater motor working again. I am also not an expert with electronics I don't know if the original magnets inside the housing with effect the performance or longevity of the new motor, time will tell.
After playing around with mounting options I decided to simply mount the new motor inside the old motor housing. The magnets still being glued to the housing meant that the motor was quite firmly held in place, with about a 1mm gap around the new motor, not bad. The tabs that used to secure the cap and brush housing on the motor work excellent to center the new motor, new wiring was soldered onto the new motor as well and routed out the top of the housing.
The fan fits the existing shaft on the motor without modification, the new motor has a "D" shaft instead of the original round shaft but the grub screw seats on the new shaft without issue. I added rubberized and adhesive backed pipe insulation foam (two pieces back to back making a thicker piece with no exposed adhesive) and it centers the motor well. A zip tie was added for wire routing away from the fan.
Testing the security of the motor:
Install is no different than the OEM unit, I used a section of the old wiring and bullet connector for visual originality.
Its summer and I have not tested the output of the unit, I also have no working OEM motor to compare it to. If I had to do it again I would have found a 750-1000 rpm motor instead. Hope this helps someone get their rear heater motor working again. I am also not an expert with electronics I don't know if the original magnets inside the housing with effect the performance or longevity of the new motor, time will tell.
