blower motor, intermittent starting problem

Flangehead

Hey guys went on a call, forced air furnace, blower motor marathon motor, no capacitor, intermittently, motor tries to start and hums, give the pulley a little push and she takes off. Motor replace 1.5 yrs ago, oiled bearings, belt alighment and tension looks good, motor and fan spin freely by hand, as I said the motor does not always have a problem starting up, just occasionly, I'm thinking possible dead spot in the motor windings?

clammy

chk capacator

Chk capacator with a cap teaser supco has a good inexpensive one or just replace the cap with one with the same rating s graingers usually carries most common caps peace clammy

Flangehead

no cap on this one big guy

lchmb

ohm

ohm the motor out looking for flat spot's. I have a feeling you will find one. If unsure how, take the power lead's off, attach a good meter and turn the motor very slowly looking for spike's or large drops in the ohm reading....:)

Flangehead

Thanks that's the answer I was looking for

tim smith

motor starting

Could also be a dirty start switch sticking periodically. Not very repairable but gets you in the right direction.

Empire_2

Motor

I agree with dead spot. Change out to PSC motor instead of Shaded pole motor. Also watch your HP. your motor is probably 1/5 hp motor. go with 1/3 or so.

Dale

Check voltage

Check the voltage to the motor on start, a bad relay contact or fan switch can drop 20 volts or so. Also,see what the rated amps are, clip the motor to see if the current draw is normal. The start switch is a good tip, especially if over oiled.