Apparently there are two heater motors for a 52 3100. I just bought one from Classic parts and it is not correct. They only list one motor. (6 volt or 12 volt) After further review I see that LMC only sells one model for a 52. Lmc does list a second one for a delux heater, but those fit 55-59. Jim Carter has a little more accurate description. There's says 47-66, 12 volt,with a 1/4" shaft, for the recirculator round core housings. Then they list one for the delux fresh air model, 12 volt 5/16" shaft. So for us that don't know about these heater motors- measure the shaft diameter first, before ordering, because only one out of three of these parts companies tells you about or even offers the difference.
