Thorp Air Command - T18.net

I now have a fuel pump on my engine and the gascolator is in the same location as before (at about the cross bar on the landing gear). I have attached a photo for reference. The angle from the gascolator to the fuel pump seems excessive. Its about a 51 angle to be exact. Is this safe, normal, etc?

Hard too tell with the living room barko lounger in the way ! I assume you are going to use SS fuel line vs the "Cheech and Chong" rubber hose ? "I can not sign thee papars as you have broken all my fingers !" With the appropriate Aeroquip fittings (multiple angles) you should be able to keep the hose bending/angles to a minimum .

RB

Dang, you sound like my wife, always giving me grief about my lounger! She's been wanting to throw that thing out since I brought it home.

The current hoses are just water hose lines cut to length. I plan to order the appropriate pre-made hoses once I get the correct lengths. I am just concerned about how steep the fuel has to travel from the firewall to the fuel pump (the hose that I am holding in the picture).

You going to run a backup pump arent you Ryan? It would appear that the only time that might give you a little trouble is if that pump gave up. I dont run a fuel pump so Rich and those that use them would know more about it than I.......Dan

I dont want to restart a discution but the design is a gravity feed system. So no fuel pump needed.
For my part I have the same fuel pump on my engine, a electric fuel pump too and when is the time I removed all this extra stuff.
If I dont need it, I dont want it!

My 2 cents!

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Thierry
French Canadian T-18
C-FPVE #091

If I had a fuel system that would benefit from, or necessitated a fuel pump, I would have it. So far, neither T-18 I have owned has had one, and neither has ever exhibited a characteristic that gave me pause to think of installing one.

I'm a good KISSer. (Tierry - means Keep It Simple Stupid)

Ryan - my lounger, having drawn the ire of my wife for several years, graces Homey's and my hangar better than Ethan Allen could ever hope.

I do have an electric fuel pump on the firewall that feeds that uphill run of fuel line. I will be curious to see what my fuel rate tests come out to be with this setup. I hope it passes because the only other thing to do is raise the level of where the fuel line passes through the firewall.

I have my fuel pressure sender on the oulet port of the mechanical pump . With the Facet pump on (engine off) I get about 4-6 psi on the gauge . No real difference with the engine running . I turn the Facet pump off after T/O (turn it back on for landing) and still get 5-6 psi from the engine pump . As a side note when I was having carb problems I disconnected the fuel line to the carb and with the fuel valve on (no boost pump on) I was getting an amazing amount of gravity flow thru the Facet pump and the engine driven pump (check valves) ! I think we have beat to death the gravity flow vs pump issue . I just like having
positive pressure" to the carb . BOOM !

I don't think you need to raise the fuel level .

RB

Thats where I plan to put my fuel pressure sensor so thats a good reference.

Bingo!!!! there you go Ryan, Thanks Rich, we have a wealth of info here and I just knew the answer would surface!! This is the premier spot for systems on a Thorp, if you need info on how to,or info on how not to, it's all right here and all one has to do is ask.......Dan

In the end the carb is still below the bottom of the fuel tank. You have fuel pumps, don't worry about the routing/angle etc. If you've ever flown a low wing (fuel in wings ... RV for example) their pumps are working a lot harder than in a Thorp. Gravity is gravity, the fuel will end up at the lowest point regardless of routing. We are mostly concerned with routing in a pure gravity feed system to maintain the correct PSI to the carb, again as you have fuel pumps you do not need to be as concerned.

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Lee Walton
Houston, TX
N51863,N118LW
KEFD

You are right Dan, this is all good info for me. Seeing as how this is my first foray into the experimental thing, I greatly appreciate all you guys with the "know how" chiming in.