Respuestas
future
He will be able to lift the car.
I will be able to find Larry tomorrow.
I will be able to come to the party.
past
He was able to lift the car (off the child's leg).
I was able to find Larry yesterday.
I was able to come to the party
In the past tense, "He was able to..." strongly implies that he did whatever action you describe. The main exception to this is that if the speaker explicitly indicates that the action was not completed, that is understandable to mean simply that he had the ability. For example, "He was able to call home, but chose not to do so," means that he had the ability to call home, but he did not.
In the future tense, to be able to do something means that someone will have the ability to do something, but not necessarily that he will do it. We can't predict the future