I have an old Baldor grinder that's at least 80 years old. It is a cap start and run motor. So the cap is always in the circuit of the phase shifted winding. There is no centrifugal start switch. It has always taken a long time to come up to speed but these types of motors do that. However, it seems to take much longer to spin up than my newer Baldor grinder motors that are wired the same. The capacitor is a rectangular shape about 5/16ths of an inch thick and maybe 1.5 x 2.0 inches. It has a brass case with cloth covered wires coming out of the tar used to seal the case. I mention the cap construction just to give an idea of how old it is. I went through the motor a few years ago because the bearings were bad. They had rawhide seals that had dried out, shrunk, and let grit in. I replaced them with modern sealed bearings. The motor runs very smooth. Just like a grinder motor should. Today I used the grinder for about 1/2 an hour and it got pretty hot. I was not loading the grinder very much because I was just grinding points on tungsten TIG electrodes with a diamond wheel I have mounted. Still, the motor got pretty damn hot. Could a bad cap do this? I suppose there could be some shorted windings. In any case, if a bad cap could cause hot running I'll take the thing apart again and replace the cap. Thanks, Eric
- posted
3 years ago