2 weeks ago, we ran the fuel pumps for the first time, planning to do the first engine run for this aircraft in Au ....... petrol everywhere! One jet coming out of one of the fuel pumps (in the cockpit due space) and one from a leaking gascolator (located above the exhausts.). Never did like either location, and never liked the fuel system arrangement, but, hey, it's been flying like that for years hasn't it? J
(lesson ..... NEVER sit in the cockpit when pressurizing the fuel system for the first time, especially if the fuel lines run thru the cockpit. We were lucky. We had fire extinguishers and a hose at the ready, but one small spark would have seen me with very serious burns (at best) for no good reason ......) SO, out with the fuel tank, out with the fuel tank supports, out with the old pumps, all the piping and the old gascolator. . The gascolator was repairable by a minor redesign and the use of solder. . The pumps have been replaced by modern diaphragm pumps from Burson Autoparts. . The piping is in the middle of being replaced with the pumps now in parallel (were series) using 5/16 copper pipe with nut and olive fittings and short lengths of 5/16 fuel injection hose where required. . Each section of copper pipe is earthed so as to bond all of the fuel system to ground. (I silver soldered little car connector tags onto the Tee pieces and used push on connectors for the earth wires.) . I've moved the gascolator from after the pumps to before them and relocated it away from the exhausts ... now I can drain the fuel tank without running the pumps ... . There is now a transparent fuel filter from Burson close to the carby . and a restricted fuel return bleed near the carby to help minimise fuel vaporisation. . I will also be covering all the engine bay fuel hose with heat shield sleeving, again from Burson. The pumps are still in the cockpit as now is the gascolator, but there is no other choice that a week of puzzling could find,. At least the pipes run continually uphill from the gascolator to the return bleed, the fuel cut off valve is easily reached and nothing gets in the way of feet or other body parts .... And I am about 4 weeks behind my anticipated schedule...... Such is Life! Cheers Martin Martin Pearce - KR2 with Subaru EA81 + KR2 S with GMH Saturn - Both in my garage, neither registered or flying in Au ---yet! rocketdri...@optusnet.com.au
