Something is wrong with my air handler fan.

Last summer I had the motor replaced and another smaller component as well (the transformer?) And everything had been working fine.

Recently however, when I turn the fan on (even without turning heat or AC on), the fan seems to have trouble cranking up, but does eventually blow good air. But then after a few minutes, the fan slows down tremendously only giving off a trickle of air. After a few more minutes, the fan shuts off completely, with no air flow, and the motor seems to buzz.

I can then leave the fan off for a few hours, and it will start up again repeating the whole process. It does seem that while it's buzzing, the motor wants to turn the fan, but it just can't. I've tried reaching in and helping it rotate, but it just won't.

Any advice on what's wrong? I'd really like to fix the problem myself and am confident with the right guidance, I can.

Thanks

With power off, see if it spins freely. If you could measure voltage and current to motor, it would tell all.

Try replacing the run capacitor for the blower motor. Use the same value for the replacement.