Landcruiser Mystery

I have a 1987 Toyota Landcruiser (4Sp 4WD) that cannot go uphill. It has been to the mechanic twice - fixed, filled up, driven home, and when it starts to head up hill it will miss, then miss badly, then lose power completely. It usually will start up again and run long enough to turn around and park…then nothing. The only thing that has not been rebuilt is the carburetor. Anyone have any experience with this problem?

Maybe it’s time to rebuild the carburetor.