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Here is what it looks like with the header tank, pumps, and pitch servo under my left seat. The servo can be removed without removing any fuel lines or the pumps. The tank will be strapped down. I welded support and anchoring provisions under the tank and pumps. Yes, the airframe welding looks much better than my tank welding. As a note, remember to keep your magnets well away from your Tig arc. I forgot this and was having a heck of a time figuring out why I was having so many difficulties welding the aluminum tank. Its a good thing the tank is under the seat where I will not have to look at the hideous welds all the time. The good news is that there were no leaks after several days with fuel in the tank or during testing with air with the tank submerged in water.
I will likely use a flex hose to connect the tank outlet to the the primary filter. That will make servicing the filer easier. Except for the Andair supply valve the only quick 90 degree turn in the unpressurized side of the fuel supply is at the Tee near the front of the door on each side. The left side has a -8 line from the aft tank fitting all the way to the valve and the right side is still -6 but the Tee changes to -8 for the line to the valve and the interior of the fitting is less restrictive. I am also using a -8 line from the valve to the header tank. I expect the valve will be the most restrictive part of the whole system.
I used low temperature alloy to fill the tubes for making the compound curves from the Tee around the fame and to the supply valve. It works but is still difficult, especially with the large -8 lines. It tends to leave some residue behind so a good brushing is in order.
I have a separate return valve that will normally return fuel to the header tank. I can also return fuel to either of the main tanks which will allow me to transfer fuel should I desire or to return fuel to the tank I am taking it from. Returning only to the header tank would be much easier. I also have a 60 PSI check valve in between the return line just before the return valve. it runs to the header tank return. This valve opens at a tested 62 PSI and should prevent any over pressures if the return valve is placed in a position that block the flow such as Off or an in between position. Theoretically if the fuel pressure regulator were to fail (unlikely) the return valve could be turned off and the check valve might regulate the fuel pressure enough to keep the engine running.
I also plan to add a vent between the main tanks and to connect the vent from the header tank to that vent line.
All in all this is matches my original system drawing. The location of th filters makes it easy to service them. Any leaks should be smelled on pre-flight and blue stains should be easy to see. I plan to place an aluminum angle behind the tank and pumps to act as a physical protection for them and to also create a dam for any fuel leaks. This dammed in area will have a drain to the outside.
I will likely use a flex hose to connect the tank outlet to the the primary filter. That will make servicing the filer easier. Except for the Andair supply valve the only quick 90 degree turn in the unpressurized side of the fuel supply is at the Tee near the front of the door on each side. The left side has a -8 line from the aft tank fitting all the way to the valve and the right side is still -6 but the Tee changes to -8 for the line to the valve and the interior of the fitting is less restrictive. I am also using a -8 line from the valve to the header tank. I expect the valve will be the most restrictive part of the whole system.
I used low temperature alloy to fill the tubes for making the compound curves from the Tee around the fame and to the supply valve. It works but is still difficult, especially with the large -8 lines. It tends to leave some residue behind so a good brushing is in order.
I have a separate return valve that will normally return fuel to the header tank. I can also return fuel to either of the main tanks which will allow me to transfer fuel should I desire or to return fuel to the tank I am taking it from. Returning only to the header tank would be much easier. I also have a 60 PSI check valve in between the return line just before the return valve. it runs to the header tank return. This valve opens at a tested 62 PSI and should prevent any over pressures if the return valve is placed in a position that block the flow such as Off or an in between position. Theoretically if the fuel pressure regulator were to fail (unlikely) the return valve could be turned off and the check valve might regulate the fuel pressure enough to keep the engine running.
I also plan to add a vent between the main tanks and to connect the vent from the header tank to that vent line.
All in all this is matches my original system drawing. The location of th filters makes it easy to service them. Any leaks should be smelled on pre-flight and blue stains should be easy to see. I plan to place an aluminum angle behind the tank and pumps to act as a physical protection for them and to also create a dam for any fuel leaks. This dammed in area will have a drain to the outside.
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