Thread: Uneven fuel usage from tanks

I have a strange problem, I have read about this issue with tanks and reading them.

My CT seems to use the left tank to the point I cant see anything in the sight tube then the right tank starts to be used. This seems to be a common thing here in the UK, a lot of other owners have said the same thing.

It is definetly not flying one wing low, even after flight and in a perfectly level hangar with the wings level, the fuel doesn't balance out! Seems very strange to me!

I have drained the fuel off on more than one occasion to see if the fuel does come out off the right tank when the left is empty, which it appears to each time.

any thoughts on this, it seems to be defying gravity!
I did notice that someone mentioned fuel tank filters somewhere on this forum, this is something I am not aware of in the UK version (or could this be the issue?)

Trevor

Did you try switching the vent caps? WF

I have checked both vents are clear, however I will try changing them over, its worth a go.

Trevor

It won't make any differance changing vents they always drain left tank first in 400 hours and trying all differant ways of flying and it still does the same so have given up trying makes no diff to running though and will run till right tank is empty ...

Mike

Just reaching for straws with this delima, the Maint Manual shows a filter inside each tank. Can they get blocked over time? Maybe a drain test of each line at the gascololater could indicate constrained flow?

Another question? If a cap vent was blocked would the vacuum collapse the tank or fuel line?

MicroMike, it appears that you have run with empty left tank and fuel still in the right and you are OK? Am I correct that the CT will still provide fuel to engine and run with one empty tank and one with fuel remaining? If so, I gather comfort that the CT will still run with empty left tank by pulling fuel from right tank. However, this means that one must not let the available fuel in the right tank get away from the pick up tube or the engine will starve for fuel. I'm trying to visualize this but I'm thinking that it would be very important when one sees an empty tube on the left side to bias the plane to fly with right wing high AND, not let the plane get into a left side slip during any turns?

Hi Dick

Yes i am embarrassed to say i have pushed the fuel beyond the comfortable limit :>) still flying after 40 mins of NO fuel showing in left tank sight tube (15ltrs showing on right tube at start of no fuel in left ) ..i was flying right wing slightly high for the duration and i would not want to get into a left side slip ...i now treat it as when fuel disappears from left tube i am on reserve and need to land within 30 mins ...

Mike

I still think we should go back to switchable tanks at least we could monitor and manage fuel levels

If you see fuel, there is fuel.
If you don't, ..you shoud'nt be there..LAND
Mine runs fine with 7 litres only,

Originally Posted by micromike

I still think we should go back to switchable tanks at least we could monitor and manage fuel levels

yesss,,or at least a valve on the right tank
OR aileron trim..but we don't

update on own uneven emptying observations - now I think it was always me, the pilot. We flew two up for 3.2h & 4.3h stints, having started in both cases with nearly full tanks therefore no assymmetric fuel load. With less than normal effort, it was possible to keep the ball in the middle for the entire flight. That more or less closes the case for me. So it seems once you allow a fuel imbalance to develop, its pretty hard work to correct while in flight. I will continue to keep an eye on things and fill her up more carefully in future.

John ! its really not worth the effort it makes very little differance to the flying and both tanks will drain to empty in the end .I tend to fly how the plane feels comfortable and ignor the ball to a great extent , unless i am turning then i balance the ball as thats a great way to get into a spin ..

Mike