Fuel System Questions

[cdavis]

0-320e2d, Long-EZ

 

Questions:

1. I see that Rutan called for a bulkhead elbow to bring the rigid aluminum fuel line through the firewall to the Gascolator. Other people plumb the aluminum tube straight through.

 

Does anyone have any thoughts about which is best?

 

2. Plans for the electrick solenoid primer valve call for fabricating a steel Tee with two AN-816-6 male fittings and one AN916-3 fitting to connect the Gascolator, Primer Valve, and Fuel pump.

 

Does anyone know of a commercial source to buy this fitting?

 

3. I have Atkinson sight gages and will install a VM1000 with fuel flow meter.

 

I assume there is only one fuel flow meter that records total flow rather than flow from each tank. Is that correct?

 

Where do most people choose to mount the fuel flow meter? On the firewall, or somewhere else? Where in the plumbing did you locate your flow meter?

 

Thank you VERY MUCH for the help. My engine is being put back together now, and I'm ready to start pulling wires. I want to install the engine and fuel system before doing the electrical.

 

BEST WISHES

[Waiter]

2. Plans for the electric solenoid primer valve call for fabricating a steel Tee with two AN-816-6 male fittings and one AN916-3 fitting to connect the Gascolator, Primer Valve, and Fuel pump.

If your Carb has an accelerator pump (most do) then there is no need for this. Prior to starting the (cold) engine, turn on the boost pump to make sure there is fuel in the carb bowl, then cycle the throttle 4 - 5 times from stop to full. The Accelerator pump in the Carb will supply a "squirt" of raw fuel every time the throttle is moved toward the full position.

 

 

As for the other questions, My fuel line enters the firewall and goes directly to the gascolator. My fuel flow transmitter is mounted in the Hell hole just forward of the firewall.

 

Waiter

[Kent Ashton]

0-320e2d, Long-EZ

2. Plans for the electrick solenoid primer valve call for fabricating a steel Tee with two AN-816-6 male fittings and one AN916-3 fitting to connect the Gascolator, Primer Valve, and Fuel pump. Does anyone know of a commercial source to buy this fitting?

 

Never seen one. I took a steel AN834-6 (or you could use an AN804-6) T-fitting, cut off one of the short legs and tapped it for a steel AN816-3 NPT-to-flare fitting. Routed the line off the -3 end to the primer solinoid and used a AN924 bolt and small aluminum angle to secure the 834/804 fitting to the firewall.

[cdavis]

Thanks for the excellent information.

 

Does it make any difference if the Facet electric fuel pump (AC Spruce PN:40108) is mounted with the hose fittings horizontal or vertical?

 

Same quesion on the Electric Solenoid Valve (AC Spruce PN: 05-29823).

 

Thanks again for the help.

[argoldman]

Thanks for the excellent information.

 

Does it make any difference if the Facet electric fuel pump (AC Spruce PN:40108) is mounted with the hose fittings horizontal or vertical?

 

Same quesion on the Electric Solenoid Valve (AC Spruce PN: 05-29823).

 

Thanks again for the help.

 

Possibly not-but then again, possibly.

 

However remember that the facet pump is a pretty good pusher and not a great sucker. If possible you want the inlet to be as close to the fuel level, if not below it, as possible.

 

The solonoid-type action of this pump is not the direct motivator for the fuel pressure. The solonoid action retracts a piston like device against a spring. It is the spring pushing the piston that does the pumping. Different spring rates determine the pressure capacity of the pump.

 

Speaking of pumps I am getting pumped up for OSH