05-21-2018, 11:44 PM
Hi Max. Thank you so much for taking the time to investigate this! The hose that I inspected for blockage is the one attached to the bottom of the tank, right near where the fuel line attaches. I believe this is the only vent line on the tank, so it must be the same line that you are describing. If you're able to draw air out of this same tube, unrestricted, then that means that your fuel cap is vented, and is operating properly. Because my tank is developing a vacuum as the fuel drains, then this means that my fuel cap is not venting properly, does this make sense? I will look for the tube that you described and see if I can draw air out of it. Thanks again Max 
I was just thinking - is there a one-way valve on this vent hose, attached to the bottom of my fuel tank? I was able to blow air out of this tube, but I didn't try sucking any air into this tube - maybe I should try this? My co-worker told me his FJ1300 Yamaha had a valve on the vent line that failed, causing his fuel tank to not vent properly and it would cause the engine to die. I'm leaning towards a malfunctioning fuel cap because of the results of the tests Max performed.
I was just thinking - is there a one-way valve on this vent hose, attached to the bottom of my fuel tank? I was able to blow air out of this tube, but I didn't try sucking any air into this tube - maybe I should try this? My co-worker told me his FJ1300 Yamaha had a valve on the vent line that failed, causing his fuel tank to not vent properly and it would cause the engine to die. I'm leaning towards a malfunctioning fuel cap because of the results of the tests Max performed.