I have a 1957 Chevy 3600 with the 235 engine, and it's been running very poorly. It will start up fine and revs good in neutral but when I try to drive it is when it runs very rough. It won't go above about 1500-2000 RPM and eventually stalls out, but will start up again just fine. I've also noticed from the plugs that's it's running a bit rich even with the carb mixture set very lean.
Some things I've already did to try and fix it:
Checked timing
Checked compression (All around 130-140)
Adjusted valves
Adjusted points gap (points are just a year old)
New vacuum advance which works fine
New fuel pump and fuel filter
New spark plugs and plug wires
Replaced intake manifold gaskets
I've also taken apart and cleaned the carburetor. I also tried using a second carburetor that I had which made no difference, so I would say my carb checks out, but with either carb on it still runs rich (both carbs have been rebuilt before) I also made sure the hole on the bottom of the carb lined up with the cutout on the insulator which it did
I don't have much experience with these engines so I'm pretty stumped on what to do now. Any advice would be great, thanks!
