----[Please read http://ercoupers.com/disclaimer.htm before following any advice in this forum.]----
Steve, after running the engine for about two/three minutes, shut down ,
and remove the header tank cap, and measure the fuel level with a clean wood
stick. The fuel level should be up to about 1 inch below the top of the
tank..(Not the top of the filler). Using a flashlight, you can probably see the
fuel level, and closely see the overflow tube close under the filler on
the rear side of the tank. The overflow line goes back to the wing
tanks.
Bad float cork is probably the problem, as Wm Bayne pointed out. If so,
either replace the cork, or dry the old one thoroughly and reseal...again
letting it dry for several days before putting back in the tank.
BUT, if this just started happening, and just after the annual inspection
which required cleaning of the fuel pump screen; the problem may be that the
fuel pump cover was not properly torqued so the gasket does not seal, allowing
air to be sucked in, instead of fuel. (I have seen several fuel pumps
replaced due to this...no problem with the pump, just a too loose cap,
allowing air to be sucked in, reducing the fuel pump capacity).
The 1/4 inch bolt requires a torque of 30 +/- 5 INCH lbs. . (See AD
81-07-06, and Continental Service Bulletin M81-8R1. Quote: " step 5.
Reinstall fuel pump cover with a new cork gasket, p/n 643915 and bolt gasket p/n
643914. Torque bolt to 30 +/- INCH lbs." Step 6. re-safety wire the bolt.
There is another possibility of a fuel return line failure IF your coupe
has the return line STANDPIPE mounted in the bottom of the tank, instead of the
return line mounted on the upper rear wall of the tank. (Most of these have been
changed to the rear wall fitting). The standpipe system sometimes failed as the
pipe actually failed from vibration, cracking the pipe at the bottom of the
tank, allowing fuel to drain back to the wing tanks.
To observe, have a look at the bottom of the header tank, where the fuel
cut off valve is..( going to the Carb). In the Standpipe system there are three
pipes located here in a triangle shape.....one is fuel inlet from the fuel pump;
the second is the overflow standpipe; and the thrid is fuel outlet to the shut
off valve, going to the carb.
If this system is installed, and the standpipe is cracked, the header tank
would probably always drain down when the engine is off, even with the
shut off valve closed.
Hope this helps.
Fly Safe - Have Fun
Harry Francis
Elliston, VA
N93530
============================================================================== To leave this forum go to: http://ercoupers.com/lists.htm Search the archives on http://escribe.com/aviation/coupers-tech/
