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Good Morning fellow Coupers, I am experiencing a similar problem with my Coupe. It is still a work in progress, however I do run the engine each month. I fill the fuselage tank and after sitting for a week the fuel goes down. The wing tanks are not connected, so I am assuming the fuel is evaporating. There does not seem to be an obvious leak. Could it be evaporating through the connecting lines that go to the wing tanks? I just bought a second Coupe that should greatly assist in putting mine into an operable unit. Thanks and have a most Merry CHRISTmas. Lee Browning N94815 On Mon, 12 Dec 2005 00:00:57 -0800 Ercoupe Hangar Flying <[email protected]> writes: > ----[Please read http://ercoupers.com/disclaimer.htm before following > any advice in this forum.]---- > > > Message list: > > 1. [COUPERS-FLYIN] Header tank question > 2. RE: [COUPERS-FLYIN] Header tank question > 3. FW: WRB Re: [COUPERS-FLYIN] Header tank question > > Messages: > > From: <[EMAIL PROTECTED]> > To: <[email protected]> > Reply-To: <[EMAIL PROTECTED]> > Subject: [COUPERS-FLYIN] Header tank question > > My header tank quantity indicator (cork on a stick) works fine. I > shows full when the tank is full and shows appropriately less as > fuel in that tank starts to burn off. If the plane sits overnight > with a full header tank, the indicator will show slightly less then > full the following morning. As soon as I start the engine ( and the > fuel pumps starts working), the indicator goes back up to show a > full tank. If some fuel leave the header tank overnight, where does > it go? > > Thanks. > > Glen Davis CFII > Grumman Tiger N70GD > 1946 Ercoupe N3103H > |-----| > _________(*)_________ > o o o > > ---------------------------- > From: "Ed Burkhead" <[EMAIL PROTECTED]> > To: "Cflyin" <[email protected]> > Reply-To: "Ed Burkhead" <[EMAIL PROTECTED]> > Subject: RE: [COUPERS-FLYIN] Header tank question Glen, When the engine is running and the fuel pump is pumping, fuel is continually flowing into the tank. However, fuel barely flows through the standpipe overflow tube when the fuel level is exactly level with the opening of the tube. There needs to be some "head" in the form of a higher fuel level before the out-flow matches the fuel pump flow. When you turn off the engine, it takes a bit of time for the flow to come down to the exact level of the overflow tube opening. Good observation. Ed Burkhead http://edburkhead.com ed @ edburkhead.com From: William R. Bayne [mailto:[EMAIL PROTECTED] Sent: Sunday, December 11, 2005 9:54 PM To: Ed Burkhead Subject: WRB Re: [COUPERS-FLYIN] Header tank question RLYFLYIN Hi Glen, Ed is 100% correct. I envy his clarity and brevity. The original "cork on a stick" has no frame of reference by which the pilot would be aware of your described difference between "full" and "slightly less than full". I presume, therefore, that you have the "Rain-Pruf" type with the exterior protective tube; and further presume that someone has marked the "full in flight" level from which the slightest drop becomes evident. The specified fuel pump moves WAY more fuel than the engine can burn at any power setting. Even after it is throttled by the 1/16" orifice in the pump outlet fitting, there is excess fuel pumped by design as a safety "fudge factor". When the engine is operating, the "normal" fuel level maintained is determined by the "standpipe", or height of the open end of a fuel line near the top of the fuselage tank interior through which excess fuel is returned to one or both wing tanks (depending on the tanks and lines installed). If the noted difference were significant, it could be that someone has removed the restrictor fitting from your plane or enlarged the hole in it to compensate for a worn-out pump. The fuselage tank standpipe can be bent or partially obstructed. Any of these conditions would amplify the difference in level after shutdown. Other than the (rather common) "ramp drip" loss out of the carburetor (avoidable if you shut the engine down by turning off the behind-panel fuel valve and running the carburetor dry), excess fuselage tank fuel returns to the wing tanks. Regards, William R. Bayne <____|-(o)-|____> (Copyright 2004) ============================================================================== To leave this forum go to: http://ercoupers.com/lists.htm Search the archives on http://escribe.com/aviation/coupers/
