Engine compartment fuel line

[Nev]

I’m about to order a fuel line from the firewall bulkhead to the fuel pump and I’m concerned about minimising the heating of the fuel going to the fuel pump. I’ll get a heat sheath on the line regardless.

It appears that I have 2 choices :

• a shorter 22 inch fuel line that runs close to the exhaust and oil cooler outlet
• a longer 34 inch line that routes higher and away from these heat sources.

Thoughts ?

[Mark Goldberg]

How close to the exhaust would the short run of fuel line be? Mark

[Nev]

How close to the exhaust would the short run of fuel line be? Mark

About 1 to 1 1/12 inches away from the exhaust at the bottom of the firewall Mark. It would also have the discharge air from the oil cooler on the fuel line if I choose this shorter routing.

The alternative routing would take it up the left side firewall above the oil cooler and well away from the exhaust, then along the firewall to the fuel pump. However with the bend radius’s required it does mean a longer line. Wondering which option is less susceptible to heat exposure.

[davzLSA]

Nev here is what I would be concerned about, if its that close to the exhaust and you have a crash landing you can be guarantied a fire if the line breaks, if it just get hot then you got vapor lock to worry about. If it were me I would get it as far away from an ignition source as possible and try to insulate the line as much as possible to mitigate the vapor lock problem. Just my 2 cents but I would defiantly look at priorities.

[Bcone1381]

In my humble opinion, Tom at TS Flight Lines is the expert on Fuel Lines. https://www.tsflightlines.com/

I know NZ is a long ways away. If you give him a call, Tom will probably be the one answering the phone. He is into solving all kinds of issues we experimental guys have. I would expect him to give you an answer, or give you a solution that involves a product you meat not be aware of, like insulated fire sleeved product made for that special issue.

With that being said, if you route that fuel line within an inch of your exhaust, will this cause you ongoing doubt and concern in the future, or are you the kind of person who can forget about it and move on? If it will cause ongoing concern, then go with your gut and take the long route away from the hot stuff.

[robcaldwell]

I 2nd Brooks recommendation for Tom Swearengton @ TS Flight Lines. He built all of my fuel lines.

(843) 271-2329‬.

tsflightlines@gmail.com

[zkelley2]

I wouldn't route it that close to the exhaust, but I also would not route it uphill to get to the first fuel pump either, or at least very minimally.

[BravoGolf]

My fuel line on the RV runs from the red cube on the fire wall to the carb over the exhaust system. I installed a heat shield on the exhaust to deflect the heat. Here is an example

https://shop.vansaircraft.com/cgi-bi...t=heat-shields

Here is a poor photo of the installation, you can see the shield below the fuel line. Look just left of center at the bottom of the photo. It’s been working fine for five years now

95CD305F-2081-4189-BA93-7D23028E5145.jpeg