I like this answer!
Right. “He” in that puzzle refers to
Helium (He)
Was ‘the few hours later’, i.e. the amount of time, needed to fix the problem.
Did the time lapse itself fix or help fix the problem.
You should have mentioned that earlier. That just made your puzzle twice as awesome. 
Oho, now that is a good twist, Biotop! It’s a shame that it only works in print, not spoken.
For the spoken version, I’d use “they,” which could be a singular they for a unspecified gender of sailor–or just whoever filled the balloon.
Not as cool, of course. But it would still work.
And the best part is that LHOD, in his restatement, managed to avoid replacing “He” with “Popeye”, leaving an answer of “yes” as still correct.
Were the repairs done to the vehicle towing the car?
Is the problem that he can’t remove his car from the tow truck?
Did this happen a long time ago, back when cars used to vapor lock?
Was Jeff too embarrassed to admit he ran out of gas and told the mechanic his car wouldn’t start and his gas gauge was broken?
Totally!
The car’s fuel supply was sufficient.
The problem is not due to a difference between the driver and the mechanic. The height, weight, or volume discrepancies between the two have no bearing on the problem. The problem doesn’t arise so much as it arose and now it’s a constant.
The time lapse did not fix the problem. There was a real mechanical failure and the mechanic used materials and his knowledge of cars to fix it once he understood.
Yes.
There is nothing physically stopping him from removing his car from the tow truck.
Vapor lock is not a concern in this case.
Jeff’s gas supply was fine and he wasn’t embarrassed to admit to the problem.
Is having his car attached compensating for the something that is broken on the tow truck?
Is he using the car for lights?
Is he using the car to compensate for problems with one or more wheels of the tow truck?
Yes, no, and yes(?). How strictly are you defining wheel?
Did Jeff’s car have a breathing attachment to his engine that prevents it from starting if alcohol is detected on his breath?
Was it the brakes on the tow truck that were broken?
If it was the brakes, did Jeff have a second person to operate the brakes on the car being towed?
If not the brakes, was the steering wheel broken?
Nope!
Yes.
There was a second person and the steering wheel was not broken.
OK. To put a bow on it, I think. Jeff realized the brakes are broken on the tow truck. He can’t tow the tow truck with his car, but he can tow the car with his tow truck and use the brakes of the car to stop both (sounds dangerous).
He gets a second person to sit in the car who is responsible for braking. Alternately, Jeff sits in the car and brakes. Some signaling may be involved between the two people so braking occurs at the right time. Jeff has to explain to the mechanic that the tow truck needs work, not the car being towed. They both have ice cream at lunch.