I have a 1956 Willys Cj3 jeep that starts and drives fine when on the level and the engine is not overworked. After installing a new radiator and carbuetor, I went on a pasture ride that gains 900 feet in 1/2 mile with very rough terrain. About 3/4 the way up, the jeep died and would not restart. The fuel pump bulb was empty and bubbling on the side nearest the engine block. When I removed the air intake from the Carburetor and tried to restart, there was never any gas in the carburetor. I need some help with diagnosing this problem. Any ideas what I am doing wrong to have this problem. This is the reason that I replaced the radiator and the carburetor as the same problem at the same place in going up the hill/mountain. Thanks, Docjoc.