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Electric Motors/delco model a4380. 220v 1hp 1ph


hello i have a old southbend lathe with a ge 1hp motor, it had 3 wires going to it,coming from a rocker type switch for forward and reverse.not sure what happen to it,it does seem to go as fast and it got hot and grease was coming out,still worked but didnt seem right. i pulled the belts off and it seems to spin really smooth. A friend gave me this delco 1hp motor that had 4 wires coming out of it,2 wires where wire nutted together and the other 2 went to a whip to be connected to power, no matter which way i wired it it would only go one direction i need it to go the other direction for my lathe. it vibrates alittle to, it has a higher rpm than my original motor,can it be wired externally to go the other way or should i get my other one looked at?my old one had a plate where the white and black hooked to and the red was wire nutted to another one inside the plate and it seemed loose,could that have been the problem with my old one? thank you i know my question was long but i wanted to be thorough.


Go have the existing motor looked at,  this is a COMMON problem with motor applications,  it is assumed that a motor is a motor is a motor is a motor,     Your existing motor with three leads most likely had two runs and one start,       the reverse process was to move the start from one run to the other,     four leads, with two tied together  or two on line    is dual voltage   non reversible,          all that is brought is the run windings,     

If you had a loose connection let's hope that was it, and likely is,        

When dealing with single phase,  AC   black or white, makes no difference,       DC polarity makes a difference,    AC   the motor is not effected which is hot and which is neutral,    

Let me know what the diagnosis is for the existing motor,  

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Three phase/ AC DC single phase motors, controls, any problems or failures, motor installation, performance issues, connections. All other electric motors/gearboxes/apparatus. Specialty repair concerns, obsolete motors and solutions. Other mechanical or specialty equipment. See my profile under Home/electrical at this site


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