Quote Originally Posted by trayson View Post
So what are you thinking? Disconnect the fuel line that goes out of the fuel filter from the fuel pump and put that into a gas can?
Yep, you want a line straight from the external gas can into the mechanical fuel pump. That existing line from the fuel filter housing to the fuel pump is pretty short, but it may be long enough.

You may have to get some extra fuel line anyways to do this test. I'd just go ahead and replace your fuel lines. It really isn't that difficult, just a little annoying because mine had all these plastic clips w/ screws that held the fuel line close to the side of the bilge. Assuming you haven't replaced them since you got the boat, i'd just do it and have peace of mind and be done with your lines.

Now i'm going to start spitballing: Concerning the potential vapor lock issue, (essentially your gasoline boiling somewhere along the way, typically inside the fuel pump). What degree thermostat are you running, 143 or 160? And following that, what's your typ. operating temperature? I have the 143 in mine. You could always try running your engine cooler, and see if that helps the issue. Having tried both degree thermostats (and one time putting a thermostat in upside down), the engine temp is obviously related to the temp inside the dog house. If you keep the engine cooler, the fuel pump, etc. stays cooler. As a test, you could just take the thermostat out and run it around for a while and see if the problems resurface. I wouldn't suggest doing this all the time as your engine isn't meant to continue running that cold.

It also could just be the fact that your fuel pump is beginning to give way and just isn't creating the amount of pressure required at higher rpms. I replaced mine, and I took apart my old one and the seals and gaskets on it were in bad shape. I'm guessing from gas w/ ethanol in it. You could always pull your fuel pump and open it up and see what it looks like.

Diagnose and replace the cheap things first....rinse and repeat.