Most likely is that it will run erratically, run hot and may burn out.
You have to access the motor to test it but it probably is bad. The brushes in the botor hangup a lot and when this happens it quits.
A loud knocking noise in the motor of a car at high speeds is most likely the engine. There could be another issue with the transmission if the knocking only happens at high speeds.
The motor will run at a higher rate of speed than normal. The extra voltage will in time destroy the motor.
To connect mechanical load to a motor, you couple it to the shaft of the motor.
The blower motor speed resister is burned out.
Connect the sunroof motor with the sunroof motor retaining bolts. Connect the sunroof linkage. Connect the wiring harness to the back of the sunroof motor.
On a three wire supply system if you connect the two 110V wires together and they are across the phase they will short out and trip the breaker. If the two 110V wires are supplied from across the phase and connected to a motor then the motor will run. If the 110V wires are on the same phase nothing will happen.
By connect a starter motor backwards I assume you mean put the negative cable where the positive cable would go and then put the positive cable to the negative connection. In that case the starter motor should run backwards. That might be a handy thing to do if you are using a starter motor to power something else such as a winch or maybe a pump.
Because your motor is spinning faster at higher speeds causing higher rpm's
change the blower motor resistor . this controls the speeds . thanks paul
Probably the blower motor speed resistor is partially burned out.
usually the blower motor resistor pkg. located on or near the blower motor