As Geof says, it could be the switch, usually they go open, and this usually means it will not start unless you give the shaft a spin, if it is shorted, the start winding stays in, as geof mentioned.
If this is the case, you could put a jumper in series with the cap lead, and when it is up to run, whip the jumper off, this will effectively remove the start cap & switch from circuit .
If it still continues to judder, it could be a winding problem.
Some lower torque motors, have a cap in circuit all the time for start & run.
Al.
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CNC, Mechatronics Integration and Machine Design.
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E. |