Fuel in the header decreasing with fuel in mains

07 Dec 2016 17:33 #727 by Ben Hacker
Replied by Ben Hacker on topic Fuel in the header decreasing with fuel in mains
Hi Steve,
First let me say that I am no expert here but have had previous problems concerning fuel in the two coupes that I have owned.
My first coupe experienced the cork float in the head tank becoming "gas logged" due to the cork coating becoming compromised from possible alcohol in the fuel and sinking rapidly but with the tank full of fuel. We ended up installing a metal float to ensure that the problem never occurred again. I assume that your tank was indeed low when you say your float indicated low fuel in the head tank (?). My other experience was with my current coupe. When I bought it, it hadn't flown for about 3 yrs and the fuel pump would not pump fast enough to keep the head tank full. We rebuilt the fuel pump we believe that the check valves were sticking or leaking. We replaced both valves and the diaphragm. I'm betting your problem is with the pump again, especially after you relating your story of the float disintegrating and particles floating around. I know you said that things were cleaned good but it wouldn't take a very large particle that might have been overlooked to get stuck in one of the pumps check valves and causing problems. Please let us know what you find........

Please Log in or Create an account to join the conversation.

21 Nov 2016 09:20 #687 by Stephen Freeman
Fuel in the header decreasing with fuel in mains was created by Stephen Freeman
On a recent trip from Texas to Tennessee the fuel in the header tank started decreasing after 2 .5 hours of flight. The first time I was close to the leg destination and landed with fuel still indicating on the sight gage. On the final leg of the trip at 2.5 hours the fuel gage started down rapidly ( I understand that the shape of the tank causes the indicator to go down more rapidly). Both times it happened at the 2.5 hour point and both times I still had fuel in the wing tanks, the wing quantity gage was very close to the bottom but still bobbing some. On that second leg I landed 20 miles short of destination because the header gage was at the bottom of the indicator (trust cork indicators). During the next legs after refueling the fuel system operated as designed both times. Has anyone had a symilar problem?

I have had previous fuel problems. The previous owner installed a plastic bobber, purchased from Aircraft Spruce, in the header tank The bobber was a Model T ford part and apperently not suitable for aviation fuel. The bobber disintegrated leaving small pieces of plastic in the header tank that found there way to the carb. After a failed fuel pump overhaul, carb overhaul and a header tank cleaning, I thought the problem was solved. This may have nothing to do with the current problem but it needs to be concidered.

Steve Freeman

Please Log in or Create an account to join the conversation.

Time to create page: 0.132 seconds
Powered by Kunena Forum