If he is weak tight like you say....I would put him on a range of hands from 2-2 to J-J, suited A-low, suited connector.
From the way he played his hand, I would say A-6, A-8, maybe pocket 4's, or even suited 5-7 are the most likely. The all-in raise would worry me here since I would be drawing dead to a Q if he had trips, and would be drawing dead if he had a straight. I know there is a lot of money in the pot but I would lean to folding since you would still have over 2k in chips left and the blinds are still relatively small since if he actually does have a made hand then you are out of the tourney.