Had just got done rebuilding a HS50 Tecumseh on a wood splitter. It started right up and ran perfect. The only thing was it would only run for about 5 min's and the engine would quit running. One pull with the rope and it would be running again with the same problem over again. I was thinking a fuel problem but everything was new. So being desperate I just ran a bypass fuel line right to the carburetor and problem solved. The only thing that I added to the fuel line was a new shut off valve. The shut off valve was made in China and for some reason the fuel would stop flowing through the valve after I would run the engine for a short time. Who would think you could have a problem with a simple fuel shut off valve. Just more Chinese junk to watch out for.
Chineese junk parts
