lennox AC condenser Fan running backwards
Your capacitor is too small.  The new motor you list requires a 10 MFD capacitor to run at 240 VAC.  Since the OEM capacitor in the unit is only 5 MFD, the new motor will randomly run backward and it will run with far less than its rated HP.

Also, you should connect the new motor to run on LOW (red wire).  These universal replacement condenser fan motors are not really multi-speed motors.  They are actually multi-horsepower motors.  At the low setting, your new motor is 1/5 HP.  The OEM motor was 1/10 HP, and the fan blades for your condenser are sized for the 1/10 HP motor.  When you install the correct new capacitor for your new motor, I think you will find that your condenser fan runs faster with the new motor on LOW than it did with the OEM motor.