skippydiesel Posted January 19, 2022 Share Posted January 19, 2022 11 minutes ago, onetrack said: ---------------------------------------------------------------- I think Skippys on the right track, a standard petrol engine, electric fuel pump with a simple pump wiring arrangement (that has to be explosion-proof, of course) is a better way to go. Always a concern. I hope that the pump/motor unit itself is reasonably "explosion"/ignition proof, in that it is a sealed and specified for petrol transfer. I have added an on/off switch (sealed using self annealing tape)on a long lead, so I can hold deliver nozzle one hand switch in other & monitor fill level. I also added a separate earth lead, with clip, to aircraft system. The system is connected to an Anderson plug under my instrument panel - always connect up befor opening fuel drums & only disconnect after replacing fuel tank/drum lids I fuel with hanger door open,for good ventilation and try to reduce chance of spark at delivery point by having nozzle well into filter funnel. At the end of the day this is an experimental system, that may have an elevated chance of petrol fume ignition. 1 Link to comment Share on other sites More sharing options...
kgwilson Posted January 19, 2022 Share Posted January 19, 2022 5 hours ago, walrus said: RF, yes, something like that but with an important addition......... Where I need to place the fitting in the fuel line, I cannot absolutely guarantee that there will never be negative pressure (ie a little vacuum) in the line. Its a gravity feed to the fuel pumps but they are EFI pumps and they suck, if you know what I mean. I have yet to find a dry break coupling that will guarantee that it remains leak proof under vacuum. As you can guess, I don't want any air to leak into the fuel system ever! The solution, I think, is a mini ball valve behind the dry break fitting that remains closed unless the fitting is in use. An outboard motor fuel fitting will do that. I have them just inside the fuselage so I can remove each wing & whatever fuel is in the tanks stays there including the line right up to the fitting. Cost me $90.00 for 2 male & 2 female Yamaha outboard quick release fittings in 2013. Probably about $120.00 or more now. De-coupling hardly spills a drop. Link to comment Share on other sites More sharing options...
kgwilson Posted January 19, 2022 Share Posted January 19, 2022 5 hours ago, walrus said: RF, yes, something like that but with an important addition......... Where I need to place the fitting in the fuel line, I cannot absolutely guarantee that there will never be negative pressure (ie a little vacuum) in the line. Its a gravity feed to the fuel pumps but they are EFI pumps and they suck, if you know what I mean. I have yet to find a dry break coupling that will guarantee that it remains leak proof under vacuum. As you can guess, I don't want any air to leak into the fuel system ever! The solution, I think, is a mini ball valve behind the dry break fitting that remains closed unless the fitting is in use. An outboard motor fuel fitting will do that. I have them just inside the fuselage so I can remove each wing & whatever fuel is in the tanks stays there including the line right up to the fitting. Cost me $90.00 for 2 male & 2 female Yamaha outboard quick release fittings in 2013. Probably about $120.00 or more now. De-coupling hardly spills a drop. Link to comment Share on other sites More sharing options...
kgwilson Posted January 19, 2022 Share Posted January 19, 2022 5 hours ago, walrus said: RF, yes, something like that but with an important addition......... Where I need to place the fitting in the fuel line, I cannot absolutely guarantee that there will never be negative pressure (ie a little vacuum) in the line. Its a gravity feed to the fuel pumps but they are EFI pumps and they suck, if you know what I mean. I have yet to find a dry break coupling that will guarantee that it remains leak proof under vacuum. As you can guess, I don't want any air to leak into the fuel system ever! The solution, I think, is a mini ball valve behind the dry break fitting that remains closed unless the fitting is in use. An outboard motor fuel fitting will do that. I have them just inside the fuselage so I can remove each wing & whatever fuel is in the tanks stays there including the line right up to the fitting. Cost me $90.00 for 2 male & 2 female Yamaha outboard quick release fittings in 2013. Probably about $120.00 or more now. De-coupling hardly spills a drop. Link to comment Share on other sites More sharing options...
kgwilson Posted January 19, 2022 Share Posted January 19, 2022 5 hours ago, walrus said: RF, yes, something like that but with an important addition......... Where I need to place the fitting in the fuel line, I cannot absolutely guarantee that there will never be negative pressure (ie a little vacuum) in the line. Its a gravity feed to the fuel pumps but they are EFI pumps and they suck, if you know what I mean. I have yet to find a dry break coupling that will guarantee that it remains leak proof under vacuum. As you can guess, I don't want any air to leak into the fuel system ever! The solution, I think, is a mini ball valve behind the dry break fitting that remains closed unless the fitting is in use. An outboard motor fuel fitting will do that. I have them just inside the fuselage so I can remove each wing & whatever fuel is in the tanks stays there including the line right up to the fitting. Cost me $90.00 for 2 male & 2 female Yamaha outboard quick release fittings in 2013. Probably about $120.00 or more now. De-coupling hardly spills a drop. Link to comment Share on other sites More sharing options...
kgwilson Posted January 19, 2022 Share Posted January 19, 2022 5 hours ago, walrus said: RF, yes, something like that but with an important addition......... Where I need to place the fitting in the fuel line, I cannot absolutely guarantee that there will never be negative pressure (ie a little vacuum) in the line. Its a gravity feed to the fuel pumps but they are EFI pumps and they suck, if you know what I mean. I have yet to find a dry break coupling that will guarantee that it remains leak proof under vacuum. As you can guess, I don't want any air to leak into the fuel system ever! The solution, I think, is a mini ball valve behind the dry break fitting that remains closed unless the fitting is in use. An outboard motor fuel fitting will do that. I have them just inside the fuselage so I can remove each wing & whatever fuel is in the tanks stays there including the line right up to the fitting. Cost me $90.00 for 2 male & 2 female Yamaha outboard quick release fittings in 2013. Probably about $120.00 or more now. De-coupling hardly spills a drop. Link to comment Share on other sites More sharing options...
walrus Posted January 19, 2022 Share Posted January 19, 2022 Yes, KG, that will work. In my case I cant guarantee I wont have negative line pressure at some time and the consequences of air in the fuel injection circuit are potentially catastrophic. Hence an isolation valve behind the dry break. Link to comment Share on other sites More sharing options...
BirdDog Posted January 28, 2022 Share Posted January 28, 2022 Hi All, I have used Caltex 95 in both of my aircraft (912 ULS) and have never had an issue. My aircraft at one point would have sat for 3 months. Yep the fuel would have deteriorated, but topped up with fresh, and it never skipped a beat. I use AVGAS if I am out on a big nav and need to top up. It mixes well. No issues there. Cruising at 9500 feet - no probs. I use the square jerry cans that sit on the wing and drain well. They have spout tube so does not spill much. 1 Link to comment Share on other sites More sharing options...
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