Serge, I installed sight tubes on my Renegade and on my KR. The tubes from the tank to the sight gauge must be fairly straight. If they have a loop in them, there will be a siphon effect that will make it hang up until the head gets great enough to overcome it. It took me quite a while to get it to work right. It's especially important that the top of the gauge is vented to above the fuel line in the tank. Any pressure differential will make for an error.
Jim Vance in Kansas, USA va...@claflinwildcats.com