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Fuel line routing in an RV-7A

gtmarshall108

I'm New Here
I am a first-time builder, and this is my first post.

Engine: Lycoming IO-360 M1B
Fuel injector: Avstar
Engine mount: Legacy nose gear
Exhaust: Vetterman crossover

I am trying to understand how to safely route the fuel lines of my RV-7A project. I am using a VA-136 fuel line which was supplied in the firewall forward kit from Van's. It is 23 inches long with a 90 deg connector on one end, and a straight connector on the other. The OP-22 drawing that Van's provides depicts a taildragger engine mount and it states that the 7A should be similar. But, I cannot seem to route the VA-136 line without stretching it around and contacting the engine mount or having it come so close to the exhaust pipes that I don't think a heat shield would even fit.

Has anyone successfully installed this fuel line in a configuration similar to mine? I am thinking that I should return the Van's supplied hoses and order something longer.

I've tried two different routes, reversing the orientation of the fuel line for each, and neither seems satisfactory. I've attached some pictures. You should rotate the first image 90 CW for it to make sense...sorry.

Tom Marshall
 

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Here are a couple of pics of my routing. The second one does not have it clamped. The adel clamps hold it up a bit so it won't contact the sump or the mount. I am using the updated nose gear mount though so I don't know if that engine mount tube is in the same position or not. I do remember the line touching the mount before I used an adel clamp though. I also ordered my fuel line from Aircraft Specialty but I ordered the same length as the Van's one. My setup after clamping has plenty of room between it and the heat shields. (not in pics) Don't be afraid to slightly flex the hose where you need it before tightening. Hope this helps.
 

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I ran mine similar to how Jereme has it. You don’t want that down around the exhaust pipe. I wish Van’s supplied I little longer hose but if you get the adel clamps on there to hold it closer to the sump, then it will be okay. I used large adel clamps around intakes to secure it.
 
I have run my fuel line similar to Jereme but under the dynafocal cup as suggested by Tom. P-Clamping the hose to the #4 induction tube controls the clearance to the engine mount and the sump.
 
Thanks all for the replies and pictures. I am trying to make this work, but it's not coming easily.

Jeremy: My engine mount is a bit different. Mine has a triangular brace to the outside as well as underneath the Dynofocal cup that the fuel line has to go around, robbing it of a bit of length. After reading your post, I removed the #4 exhaust pipe, re-attached the line, and mounted the Adel clamps. In my application, the fire sleeve is fully compressed and the line itself is rubbing against the engine mount as it goes around the corner. If I relieve the tension on the hose by pulling it back in the Adel clamp so that it does not touch the engine mount, it then is stretched across the sump at the front of the engine and it is a stretch to connect it to the fuel injector

Tom: You can pass the tube under the Dynofocal cup, but there is also a piece of metal welded there so the line has to pass around that as well. Length is again a problem.

My conclusion is that this fuel line, for whatever reason, is a bit
short for my needs. My goal would be to have it routed so that does not rub against anything, and it is not under any undue tension. My inclination would be to return it for some credit and order a custom-length line.

I've attached some pictures.

Tom Marshall
 

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Ya that length does seem a bit short. Weird because that line has been speced on the -7A for quite awhile. I would avoid the hassle and get you an order in with Tom at TSflightlines or Aircraft specialty. In fact, I have found ALL of my lines ordered from them to be cheaper than the ones from Vans. Maybe Tom will chime in on how much to add or at least how to measure for it.
 
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