I have a 2005 70 hp johnson 4 stroke that runs fine. Starts quickly and runs smoothly. The problem is that after running for 15-20 minutes at 4000-5000 rpm it stalls and goes to idle. I feel the ball in the fuel line and it is empty. If I disconnect the fuel line to my 6 gal external tank and re-attach it I can pump the ball and it fills back-up. Then I can take off like nothing happened but the stall returns after another 15-20 minutes. This has happened on two different tanks and two different fuel lines. The engine does not shut off.
Help
Help