The 266 requires the specific fuel line for the saw., the line may look snug going through the bellows located in the case but will not be snug and leak free through the opening of the gas tank. Just a heads up , thank you for taking the time to post the video, 266 are a great saw!
I own a 266XP made in Yugoslavia that is one bad boy! One of the two things that I see guys do with a chainsaw is they pull the choke all the way out as far as they can! I always push the choke back open just a small amount because, If we all remember right, A fire needs oxygen to burn! If you pull the choke all the way out it shuts the choke plate completely and it makes it hard to start. Second thing, over the years of people shortening the pull starter rope for whatever reason? They make the rope so short that you can't get a full pull! Not to mention, when it comes to the end of the spring it locks up the plastic pull starter and it's not a matter of if, It's when it breaks it your out of commission my friend! I own 70+ chainsaws and I have seen every thing that people do to chainsaws and it not as easy to operate one as one might think!
I have the same model saw and use it 3 or 4 times per year. I finally realized that it was cheaper for me to run the premixed can gas instead of gas station gas since I use less than a gallon per year. I would use the saw, and then several months later, I would have to replace the special (expensive) fuel line before I could use it again because of the ethanol.