[Gearhead999]

When you take the fuel filters out to replace them, are they dirty, clogged??

If you take the carb top off...is there dirt in there?? What is the float level??

What kind of shape is the fuel tank in??

Disconnect the fuel line at the carb. Turn the engine over with a can under the line to catch the fuel. Do you have good flow?? Is the fuel dirty??

Sounds like it is starving for fuel. To eliminate the fuel tank for test purposes you can rig up a fuel can with line under the hood. Have it so the fuel pump is drawing the fuel out of the can and running the motor on that. You have to be CAREFUL here. Gas is highly flamable. If it runs on the clean fuel out of the can and drives OK...well you know where you problem is.