Working on restoring an old Craftsman Block Grinder. Hit a snag…

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  • #538088
    Madrid, NY

    Model 397.19590, build date of Sept. 20, 2965, by Delco, a division of General Motors.


    partially done

    I had to replace the capacitor as it was leaking and during disassembly both connector tabs snapped off. Before I tore it down it worked but I had to spin the wheels to get it going, otherwise the motor just hummed(a normal indicator of capacitor problems).

    Today I got the basic grinder, sans guards and rest put together. When I first put the motor together, I fired it up to test my wiring and it seemed to work. I installed the new capacitor and replaced a baby blue wire leading from the power switch to the windings as it had gotten pinched and the insulation was badly damaged. Used a 14ga piece of the same color wire that appears to be the same size internally as what came out, I couldn’t find markings on the original wire to verify size. I soldered the wire to the windings and connected a spade plug to the switch end.

    Once I got it assembled with wheels on, I tried starting it and it had the same problem as before. When first turned on, the wheels creep backwards a little. Once you spin then up to sufficient speed the motor starts to spin them up to speed.

    After that I pulled the bottom cover of and verified all the wires were properly connected, which they were according to the wiring diagram on the bottom cover. I also noticed that the motor itself was pretty warm when I had the cover off. I’m wondering it I’ve got a bad connection on one end or the other of the baby blue wire or if I need to be looking elsewhere?

    Shop Blog: http://ravenbarsrepair.tumblr.com/
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    Honolulu,, Hi.

    The grinder looking good. Looks like there’s a lot of work there.

    Holladay, Tn

    Nice job on the restoration. I wonder if you got the wrong capacitor?


    A Working Pro since 1994!

    Member since March 26, 2014.

    Eastern shore of, Pa

    It does sound like the capacitor. Nice job on the resto

    Bloomington, IN

    Sounds like the capacitor to me as well. They help with start up speed. Perhaps the one you bought is bad?

    Jon P.
    Timber Carpentry & Construction

    west bend, wi

    I know nothing about how tools work so i will be of no help. But i will follow this as I have an OLD home built drill press I would like to get running again. Looking great so far

    Fayetteville, NC

    Nice old grinder Dustin. Came out looking really good.

    Automotive Pro
    Fayetteville, NC


    Would love to learn here some valuable things about the tools have not the right information. So still looking great so for here!

    Fayetteville, NC

    Would love to learn here some valuable things about the tools have not the right information. So still looking great so for here!

    Keep reading the posts especially the older ones. Look around there is lots of info archived on this site.

    Automotive Pro
    Fayetteville, NC

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