97 780 SLT Running Lean

[xlint89]

I have never seen the fill hose deteriorate myself. But then again, the fuel we have now is not good for rubber, so anything is possible.

I would prob lean more towards dirty gas container.

[WaveChaser]

I checked the filler hose and it is in very good condition.

I hope I have finally found the smoking gun.

[WaveChaser]

No smoking gun. Still running lean and separator running low. I am going to try a separate gas can and see if it is the tank. Cannot figure this out how it is getting air in the lines when the separator connects directly to the tank.

[K447]

- separator running low. I am going to try a separate gas can and see if it is the tank. Cannot figure this out how it is getting air in the lines when the separator connects directly to the tank.

The fuel supply unit inside the fuel tank would be the aluminum column type, I expect.

The metal column has an internal void that leads from the bottom (the actual fuel intake location) up to the top. At the top an aluminum tube/nipple is pressed in (fuel feed hose connection) and the small tube is supposed to create an air-tight seal to the extruded aluminum. If the nipple has loosened or corroded where it is inserted into the column it may no longer have a proper seal to the column.

http://greenhulk.net/showthread.php?t=141548&p=1580118&viewfull=1#post1580118

http://greenhulk.net/showthread.php?t=206966&p=2267056&viewfull=1#post2267056

[xlint89]

Hose clamps too tight and deforming the hose?

You have the O ring for the water separator?

Vents working properly? Did you try unscrewing the gas cap and seeing if that helps?

[WaveChaser]

I have tried everything. Vents work fine. I already covered the separator rebuild and O rings.

if it is the nipple leaking in the aluminum, how do you get it apart and fix it? I looked at your links but nothing how to fix it. However, i have done both pressure and vacuum checks and I cannot find any leaks. Like I said, this all defies logic.

It passes vacuum and pressure tests dry but it seems to suck air when gas is involved. If I fill the separator full of gas and then pump gas through the system with a 12v pump, the level in the separator will go down but I see no air bubbles in the supply line. It must be vary slight.

[xlint89]

Have you tried putting a vacuum pump on the pulse fitting of the fuel pump? I wonder if the diaphragm is damaged and introducing air into the system?

Did you replace the fuel selector switch?

What fuel hose are you using? What hose clamps? And how tight are they?