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MOTOR BUZZES INSTEAD OF STARTING
4

MOTOR BUZZES INSTEAD OF STARTING

MOTOR BUZZES INSTEAD OF STARTING

(OP)
HAD OLD SINGLE PHASE 2HP MOTOR RUNNING BUT SOUNDED AS IF BEARINGS WERE DRY. I SPRAYED PENETRATING OIL ONTO SHAFT AT
ENDS AND WHEN TURNED ON ONLY BUZZED LOUDLY AND WOULD NOT
START. MOTOR WILL RUN PERFECTLY IF YOU ASSIST IT IN GETTING
STARTED. CAN I REVERSE MY FOULUP OR IS THIS MOTOR SCRAP?

RE: MOTOR BUZZES INSTEAD OF STARTING

Hello Stein69

Your motor is dispalying the clasic symptoms of a single phase motor with no start winding in circuit.
This is usually caused by the centrifugal switch not operating, or the start capacitor not being connected.

Most single phase motors have a centrifugal switch that connects the start winding (with or without a start capacitor depending on the type of motor). The start winding is in circuit until the motor is almost up to full speed at which time the start winding is disconnected by the switch. The switch should measure closed when the motor is at rest.

Best regards,

Mark Empson
http://www.lmphotonics.com

RE: MOTOR BUZZES INSTEAD OF STARTING

STEIN:

That switch Marke is talkin about is inside the motor something on the shaft messes with the fixed switch ..So u have to pull the motor apart.  Spraying it *could* have affected this mechanism, gunked it up or contaminated the contacts, etc.

RE: MOTOR BUZZES INSTEAD OF STARTING

Any decent motor shop can repair that for you, it's a fairly routine job for them, not much labor involved.

"Venditori de oleum-vipera non vigere excordis populi"


RE: MOTOR BUZZES INSTEAD OF STARTING

The oil and dirt could be affecting the starting contacts or the centrifugal switch. Send it to a motor repair shop for bearings change and recondition of the starting elements.

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