Just a little background information, I'm hardly a mechanic, and I don't have anybody close to help. I have the tools and basic knowledge, but that's about it.
Got my dad's 53 out of the barn, as it had sat for about the last 12-14 years. So far, we have got it running, but not well.
I replaced the fuel tank with a plastic one (the old one was rusted horribly), made sure the engine was loose, put in fresh fuel, cleaned the points, and she fired up right away. Purred like a kitten, just like I remembered. Drove her around the farm (About 1 mile) and ran great. On the second trip, she died/sputtered. Would run at an idle, but not with any throttle. Like it was running lean/out of fuel, but I'm not sure.
I replaced the fuel filter, then I rebuild the solex carb, put in new plugs (the old ones looked great). Still the same problem. Fuel is getting to the carb - I disconnected the fuel line at the carb and it pulses with every turn of the engine, so I assume the fuel pump is not the issue, but I just don't know what is. Can a fuel pump work fine at idle but not under a load?
Some other info that might help: It starts and idles fine, and the throttle is responsive at first. Then after a few revs, it begins to hesitate and then wont rev up at all, but rather almost dies, but usually doesn't, but still doesn't recover to the point it will rev normally again. Have to turn it off, let it sit and try again.
I'm lost at this point. Any suggestions?