It’s definitely got air in the fuel I’ve gone through everything else I can think of and I assumed it had a in tank pump, I guess the plug on top of the tank is just for the fuel gauge so that’s good to know. It’s very hard to get it to start and when I can it only runs for a couple seconds. I know it has air in the fuel but I can’t get it to bleed. I’ve got 5 gallons of fuel into the tank and the selector valve is bypassed I’ve ran it down to only 1 gallon a couple times in the past without issue. I’ll try adding more fuel and see if the pickup is broken like you said.
I would start with more fuel. You may find it stalls 3-6 times after you get it running. (It takes a little to get the air out.). I usually try to hold it at 1,500rpm so the pump works faster and speeds up getting the air out.
If that does not work a trick some members do is hook a 5 gallon gas tank with a hose to the lift pump. Then see if it runs good. If so they know it’s the lines from the tank pick up to the lift pump. Know the return system is going to send some of the 5 gallons to the onboard fuel tank. (Not back to the gas can) So if the trucks tank is full you could overflow.
If that trick does not work it could be your lift pump is bad. Not sucking fuel in or not creating ~5lbs of pressure at the filter. Could be your fuel filter is plugged up. Could be the IP but less likely.
Air intrusion before the lift pump will not go away and causes no starting, hard starting, and rough running. Generally air intrusion from the return lines only effects the truck when it sits for say +8 hours. The fuel drains back and the pump has to fill the supply lines again to start. Takes a couple start cycles, idles rough or erratic, and then clears up.
Attach some pics and let us know how it goes.
