Is it worth it
 

I found a 1998 Jeep ZJ V8 4x4 it has 190,000 miles on it, its a little banged up and the guy wants 800 cash for it. It runs good the only problem i can find is it runs hot while pressing the gas but goes back down when you let off. My question is would it be worth buying and putting some money into for a weekend ride that can hit some trails with the kids or do yall think the mileage is to high? Also what do you think could be causing the engine to run hot like that?