My Stihl 029 chainsaw failed. Replace two fuel lines no help. Rebuilt carburetor no help. Found replacement fuel line was 3/8 inch too long and was kinking when installed. It fits so tight it was very hard to see kink. Cut off 1/4 inch and was able to install carburetor and now all runs fine. The original fuel hose is brittle and cracking causing no fuel to the carburetor.
Original
Original bent showing cracks better
New with 1/4 inch cut off end