'64 bug, 40hp. I've cleaned the carb, checked plugs and timing and fuel pump. Compression and valves OK. It continues to seem to back down to running on 3 cylinders as soon as any load is put on the engine. Any ideas? Please ask further questions to help me in diagnosis. I don't want to just start tearing into things.

 

Welcome to the forum.

What are the compression readings?

How have you checked the plugs only visually?

Check the distributor cap and rotor arm for any cracks.

https://volkswagenforum.com/forum/ne...gnature-34185/

 

Compression = 125 all around
checked plugs visually - all look like they're firing
will check cap&rotor for cracks.

 

Keith, Thank you. Plugs were it. I checked and cleaned everything else too. Runs like a top.