Does FD expect the header tank clear/odd size/ hose or tube, whatever that is, be changed when it becomes opaque?

[airhound]

Or is it Ok as long as it doesn’t leak. I don’t believe it’s part of a preflight checklist. Or what am I missing, it’s clear for some reason. 

[airhound]

Roger is the tube a sight gauge for header tank quantity or fuel flow, or a supply line? What is it’s primary function? 

[Tom Baker]

My educated guess is that it is for when you get a low fuel warning, that you can visually confirm it after you land. The low fuel sensor is in the top of the header tank.

[Tom Baker]

4 hours ago, Roger Lee said:

It is a sight tube.

Yep, and about as useless as tits on a boar. You can't see it from the cockpit, and when fuel is low enough to show the level in the sight tube you should have already been on the ground. It may be an ASTM thing borrowed from the regulations on standard category airplanes. "(9) Fuel gauge indicating the quantity of fuel in each tank."

[airhound]

…..or perhaps another fuel leak source as a result of a mishap with baggage stuff flying around. Didn’t know, thanks for the ideas gentlemen.

[ct9000]

4 hours ago, Tom Baker said:

Yep, and about as useless as tits on a boar. You can't see it from the cockpit, and when fuel is low enough to show the level in the sight tube you should have already been on the ground. It may be an ASTM thing borrowed from the regulations on standard category airplanes. "(9) Fuel gauge indicating the quantity of fuel in each tank."

Tom I find it helpful during maintenance when testing / timing fuel flows from each tank, other than that not much.

[Tom Baker]

9 hours ago, ct9000 said:

Tom I find it helpful during maintenance when testing / timing fuel flows from each tank, other than that not much.

Sorry, my comment was meant primarily for flying purposes. I have used it when performing maintenance.

[John]

Metric (mm) / 6 mm ID X 8 mm OD - F018120

Fractional and Metric FEP Fluoropolymer Tubing — Fluorostore

Is similar to Teflon, but clear.   Will not discolor with fuel. Should never need replacement unless damaged.

John

[sandpiper]

On 10/30/2022 at 8:17 AM, John said:

Metric (mm) / 6 mm ID X 8 mm OD - F018120

Fractional and Metric FEP Fluoropolymer Tubing — Fluorostore

Is similar to Teflon, but clear.   Will not discolor with fuel. Should never need replacement unless damaged.

John

Won't discolor? Even with mogas?

[Bill3558]

On 6/8/2021 at 8:36 PM, airhound said:

…..or perhaps another fuel leak source as a result of a mishap with baggage stuff flying around. Didn’t know, thanks for the ideas gentlemen.

 

[Bill3558]

Another way to turn off fuel to the header tank is to remove the tank selector valve cover and rotate it 180 degrees ( from both).  This turns the valve to off. 
Arian told me this one.