Thanks so much, Modified! My neighbor is jumping for joy! He has had this saw for many years and hasn’t been able to get it to run right for a long time. After your reply, I located the old duckbill and barb stuck in the bottom rear of tank. I was able to replace the missing fuel line and reinstall the vent and the runs like new again!Exactly the pulse line goes to the top of the carb. Use a good rubber line. 1/8 x 3/16 should do it.