dust Posted October 14, 2003 Share Posted October 14, 2003 OK how about a fuel flow sensor in back of the rear seat back support, shorter wire need or does it need to go between pump (suck) and engine?? Also, as we are fuel injected, i see no need for a gascolator. And anyone know of a double throw valve that will accept 1/2 inch OD plumbing? Quote maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build i can be reached at http://www.canardcommunity.com/ Link to comment Share on other sites More sharing options...
John Slade Posted October 15, 2003 Share Posted October 15, 2003 Talk to Bulent Alieve about the valve. He had a bunch made for the ACRE list recently. I'm not sure about the fittings. Quote I can be reached on the "other" forum http://canardaviationforum.dmt.net Link to comment Share on other sites More sharing options...
Wayne Hicks Posted October 15, 2003 Share Posted October 15, 2003 Dear Dust: I'm no expert on firewall aft, so I've asked a few experts and a few builders with fuel injection installations that have given them lots of trouble-free hours. Here is their concensus on the order of components in the fuel-injection system: 1. Fuel tank 2. Tank Sump 3. Fuel Valve 4. Gascolator (should be at firewall, trap any dirt before everything downstream) 5. Electric Boost Pump 6. Engine-driven mechanical pump 7. Fuel pressure transducer (Install at the available port on servo) 8. Fuel servo (The servo also has a fine screen to be inspected at annual) 9. Fuel flow transducer (could be before servo) 10. Fuel distribution spider The field was split 50/50 on the order of 4 & 5. Some have said to reverse 4 and 5 so that the boost pump does not suck fuel from the gascolator. If the gascolator gets clogged, it could cause the boost pump to cavitate, which can cause the pump to overheat and fail within minutes if not tens of seconds. As for the fuel valve, there are a number of companies that have dual port valves specifically for fuel return to the supply tank. Andair makes an excellent (but $$$) valve for this purpose. Hexadyne Aviation advertises its Duplex Fuel Control Valve in Sport Aviation and Kitplanes. Or get a valve from any airplane flying a fuel-injected Continental. Alot of the Continental engines have a fuel return line in its fuel injection system. For Lycomings, it depends on the type of fuel servo as to whether or not you need a fuel return line. (But you may be going auto engine conversion?) As for the gascolator, you NEED some type of filter to keep trash out of your fuel system. Yes, sumping the tanks catches alot of the debris. Yes, the tank screens and finger strainers prevent large boulders from getting downstream. But you do need a gascolator or some type of high-flow fuel filter. ....Wayne Hicks Quote Wayne Hicks Cozy IV Plans #678 http://www.ez.org/pages/waynehicks Link to comment Share on other sites More sharing options...
Wayne Hicks Posted October 15, 2003 Share Posted October 15, 2003 One small caveot: Be wary that some fuel select valves from Continental-equipped airplanes are made to return the fuel to only one of the tank. You really want one that returns fuel to the same tank that's supplying the fuel. ...Wayne Hicks Quote Wayne Hicks Cozy IV Plans #678 http://www.ez.org/pages/waynehicks Link to comment Share on other sites More sharing options...
Jim Sower Posted October 15, 2003 Share Posted October 15, 2003 I agree with most of what Wayne says. I would put my water drain in the sump (making sure there is a distinct low spot in the sump to put it in). The fuel is "sucked" out the top of the sump and outlet line cheats 1/4"-1/2" off the bottom. I'm not sure about coarse fllters upstream of the fuel pump. It would have to be pretty damn coarse, and transparent (so I could check it regularly) to suit me. If I had one, I would want inlet pressure at the pump to monitor it's status, and that greatly complicates wiring, instrumentation etc. I have no problem with all return fuel going to the same tank. My design entails both wings gravity feeding into the sump, parallel, checked electric pump/filters drawing from the sump and supplying the rail, return only to the right tank. I would have a Facet pump to transfer from the left tank to the right as required and to ensure late in the flight that every drop of fuel I own is in the "selected" tank. No valves at all for fuel management. I would have maintenance shut-off and perhaps a main shut-off (at sump outlet) that would be electrically closed and fail open. Quote ...Destiny's Plaything... Link to comment Share on other sites More sharing options...
dust Posted October 15, 2003 Author Share Posted October 15, 2003 I think you may be "required" to have a shut off within reach. Quote maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build i can be reached at http://www.canardcommunity.com/ Link to comment Share on other sites More sharing options...
LargePrime Posted October 16, 2003 Share Posted October 16, 2003 I am about to make 10K WAAAAHOOOOOOO!!! Quote We know who you are... Link to comment Share on other sites More sharing options...
dust Posted October 17, 2003 Author Share Posted October 17, 2003 So how do you measure fuel flow when most of it is returned to the tank whence it came from, two tranducers and a calculator?? enjoy the build Mike Quote maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build i can be reached at http://www.canardcommunity.com/ Link to comment Share on other sites More sharing options...
Jim Sower Posted October 17, 2003 Share Posted October 17, 2003 <... So how do you measure fuel flow when most of it is returned to the tank whence it came ...> Your scheme is one alternative (not an attractive one) and Tracy's fuel control is the other. He calculates fuel flow from injector pulse bandwidth and it seems pretty accurate. Quote ...Destiny's Plaything... Link to comment Share on other sites More sharing options...
mplafleur Posted October 17, 2003 Share Posted October 17, 2003 That's true. All automotive applications calculate it that way. You have to know fuel pressure and temperature. From pressure you can get flow and from temp you can get density. Then you know how much fuel is used during each injector fire. If you are carburated, then you have to use a flow sensor, but to be accurate, you still have to adjust for temperature as it effects fuel density. Quote Mike LaFLeur - Cozy MkIV #1155N68ML Link to comment Share on other sites More sharing options...
dust Posted October 17, 2003 Author Share Posted October 17, 2003 just tslked to blue mountain - two sensors and it does the math. who hoo mike enjoying the build and fuel system design Quote maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build i can be reached at http://www.canardcommunity.com/ Link to comment Share on other sites More sharing options...
Norm M Posted October 18, 2003 Share Posted October 18, 2003 RMI also has a two flow sensor module that does the math and sends an adjusted signal to the monitor. Given the injector signal, I would think that would be close enough. Regards- Norm Muzzy Quote Link to comment Share on other sites More sharing options...
dust Posted November 5, 2003 Author Share Posted November 5, 2003 fuel valve my choice for a valve (double throw, 6 pipes 3 pipes@ 1/2" 3@ 3/8") andair - 450.00 wentworth air from a piper as pictured - 50 inc freight Also my buddy, the 25 year aircraft investigator advised me to buy used as they almost never brake, none that he could remember enjoying the build Mike Quote maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build i can be reached at http://www.canardcommunity.com/ Link to comment Share on other sites More sharing options...
dust Posted November 16, 2003 Author Share Posted November 16, 2003 OK so i mispoke. The Valve is 3/8 feed and 1/4 return Out of a t360, so it is good to go I believe the next size valve is probably for the 520 or 540 engines the valves come in eithor 1/4 or 1/8 returns, i wouldn't personally use the 1/8 enjoy the build Mike Quote maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build i can be reached at http://www.canardcommunity.com/ Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.