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-----Original Message----- From: William R. Bayne [mailto:[EMAIL PROTECTED] Sent: Sunday, December 25, 2005 11:51 AM To: Ed Burkhead Subject: WRB Re: [COUPERS-TECH] Useable fuel/datum RLYTECH Hi Don, Original Ercoupe fuel lines were Resistoflex. Pressure in the gravity line to the gascolator is approximately 1 psi. Were it not for the engine compartment heat and vibration, clear aquarium tubing without clamps would easily serve the purpose. As I said, if a fuel line is reasonably flexible (not ten years + in service), and has not been "upgraded" to those massive "aircraft" assemblies with threaded fittings on each end (more weight, same function) or of the stainless external sleeve type, reasonable pressure applied as described is simply not going to precipitate the failure you suggest. If one were to take one of these hoses and attempt to demonstrate such failure, the quickest way would be to cut the line in half, try what I suggest to one piece and subject both to increasing pressure until failure. Pressure test each and report back any difference. Do you really expect either hose to fail at less than 10 PSI? A ten to one safety margin exceeds most industry standards. I see no real danger in carefully following the procedure suggested, but there is a very real danger in remaining ignorant as to your plane's useable fuel. I deem the "real" risk of precipitating the failure you describe utterly insignificant, and your implication such failure could predictably occur on the next flight ludicrous. If you're genuinely concerned as to the effect of the procedure on a hose as it ages, replace the thing with a new one once the nose tank has been drained and calibrated. No big deal. You also know that the inside diameter of these hoses is 1/4"; so if you prefer, shove a 1/4" bolt in the hose as a calibration shutoff. Happy? We all know of people who should be physically restained from handling tools. If one works on their plane, I don't fly with them. But most of us are quite capable of working on our planes to some extent. I do what I can to encourage this even as I try to point out where there be real dragons (as opposed to imaginary ones). The "Chicken Little" mentality has no place among mature adults who would enjoy the freedom of the sky but lack the financial resources to have a mechanic do everything for them. I have little patience for those who preach doomsday to all who would learn their machine through progressive study and intelligent involvement in its care and feeding. An Ercoupe isn't rocket science. Regards, William R. Bayne <____|-(o)-|____> (Copyright 2004) On Dec 25, 2005, at 8:49 AM, DONALD BOWEN wrote: > WRB wrote: > > (1)>>Wrap the jaws of a pair of Vise Grips with duct tape or > electrical tape. Apply these to the gascolator fuel line, applying > just enough pressure to close off flow. (This presumes the line is > still flexible. Replace it if it is not.) Take the fuel line loose at > the gascolator and drain precisely one-half > > > (2)>>>Catastrophic fuel loss in flight (such as fuel line failure or > loss of a fuel drain or gascolator) is too rare to worry about in a > properly maintained coupe. > > > I, for one, would not do (1) above, lest I cause (2) above - nor > would I authorize my mechanic to do so, unless he agreed to accompany > me on my next flight. > > > > Don Bowen ============================================================================== To leave this forum go to: http://ercoupers.com/lists.htm Search the archives on http://escribe.com/aviation/coupers-tech/
