This is the 5528th most frequent Turkish word.
motoru
"Motoru" means "the motor" or "its motor" in English, depending on context.
In this sentence, 'motoru' is the accusative case of 'motor' and refers specifically to the motor itself being the object of the action of repairing.
Motoru tamir etmek için bir uzmana ihtiyacımız var.
We need an expert to repair the motor.
Here, 'motoru' again appears in the accusative case, indicating that it is the object of the action of learning to operate.
Ahmet motoru çalıştırmayı öğrendi.
Ahmet learned how to operate the motor.
In this sentence, 'motoru' is in the possessive construction indicating an entity that lacks a motor, used as an attribute of the vehicle.