Routing Fuel Lines

[clemsonteg]

I am trying to decide the best approach for routing the fuel lines on my 70 SWB C10 using a Boyd tank with the in tank pump. I plan to use braided PTFE line and I may or may not incorporate some hard line to help reduce the cost.

The Boyd tank was installed when I had my SBC, and I used hard line from the tank all the way to the mechanical pump along with 2 short pieces of rubber hose to make the transition from the tank to the frame and from the frame to the pump. At the time, it made more sense to run the line along the passenger side of the frame and my exhaust down the driver side.

With the LS, it seems like the supply and return would be easier to route down the driver side, but moving my exhaust isn't really an option and I am not so sure I like the fuel lines running close to the exhaust.

How is everyone else routing their fuel lines and would you have done it differently?

[SaltyC20]

I haven't done it personally, but I have seen it in other build threads. I think you can flip the fuel rail on certain intakes. Then the fuel fittings are on the passenger side. Try googling around. I don't which intake you have.

[clemsonteg]

Originally Posted by SaltyC20

I haven't done it personally, but I have seen it in other build threads. I think you can flip the fuel rail on certain intakes. Then the fuel fittings are on the passenger side. Try googling around. I don't which intake you have.

I think that would put the fuel lines at the front of the engine. I'd have to look at the placement to see if that makes things any better

[MalibuSSwagon]

I routed my lines down the passenger side, and used the OEM type nylon lines. I came up the firewall, and around the back of the engine to the fuel rail. Wrapped the fuel lines in a heatshield sleeve and haven't had an issue.

[BR3W CITY]

"technically" speaking the way to do it would be to lift the cab off the mounts and run the fuel lines OVER the frame, which is more common on late model trucks that don't have full C or I channel frames.

I have my fuel running on the inside of the passenger rail, ~4" or less from the exhaust. Its liquid fuel under pressure, not vapor, so the exhaust heat isn't a threat. Your not going to boil fuel unless you set the damn line right on the exhaust. If you REALLY think that your getting overheated fuel, just put a fuel cooler on the firewall (I've yet to see anyone NEED to actually do that).

Heck, Honda guys still think pre-heating fuel is good (half joking, but check out some of the late 80's early 90's imports running fuel pre-heat....they like to blow up).

[clemsonteg]

Originally Posted by BR3W CITY

"technically" speaking the way to do it would be to lift the cab off the mounts and run the fuel lines OVER the frame, which is more common on late model trucks that don't have full C or I channel frames.

I have my fuel running on the inside of the passenger rail, ~4" or less from the exhaust. Its liquid fuel under pressure, not vapor, so the exhaust heat isn't a threat. Your not going to boil fuel unless you set the damn line right on the exhaust. If you REALLY think that your getting overheated fuel, just put a fuel cooler on the firewall (I've yet to see anyone NEED to actually do that).

Heck, Honda guys still think pre-heating fuel is good (half joking, but check out some of the late 80's early 90's imports running fuel pre-heat....they like to blow up).

Thanks for the comments. I'm actually not really concerned about boiling fuel, it was actually more of a concern that IF something went wrong and the line became cut or punctured it could spray pressurized fuel on hot exhaust. Probably still not a concern since the line is wrapped in a stainless braided cover.

Any reason why you picked the passenger side over the driver side?

[Ole Greenie]

Originally Posted by clemsonteg

Thanks for the comments. I'm actually not really concerned about boiling fuel, it was actually more of a concern that IF something went wrong and the line became cut or punctured it could spray pressurized fuel on hot exhaust. Probably still not a concern since the line is wrapped in a stainless braided cover.

Any reason why you picked the passenger side over the driver side?

Hey Y'all, I used AN fittings all the way to the fuel pick-up and return at the fuel rail. I had though used new OEM fuel rail connectors would hold with the rail, locking onto the fuel rail and all. I had run my lines on top of the transmission from the passenger side of the truck and it looked and worked pretty well until...

The fuel supply line came off! It had unhooked itself from the fuel rail and was hanging on by 1/2". Thankfully the engine still ran...enough so to manage an exit and a stop alongside the road. I knew something had gone wrong immediately because the cabin filled with the smell of fuel. I had shut the motor down as soon as I could and coasted to the side of the highway. I popped the hood and gas was everywhere. Those Walbro 255 pumps really do a good job at delivering the fuel!

Well, I tried to reconnect it but it popped off again. Thankfully I had a FI clamp and that got me home but I was ever so thankful that there was no fire. God was really watching out for me!

Anyway, I bought few fittings on Ebay that used a threaded cam setup to reconnect the fittings to the fuel rail. It is this one:

http://www.ebay.com/itm/131404860888...%3AMEBIDX%3AIT

and it works great. It may be a bit much @ $13.29 but it is insurance against a fuel fire. I would recommend using these not only on your fuel rails but on your fuel filter if you use the 3/8" OEM style filter. Hope this helps someone out there who is considering the OEM style fuel rail and fuel filter connectors. Simply said...they suck...kind of like the exhaust manifold bolts that GM never addressed. That is another peeve...

Best to you all...especially Jonathan who sent me an engine cover bracket. Y'all, Jonathan sent it to me...no payment, no shipping, no nothing. He is a good man!

John

[FarmerSid]

I am going to run my fuel lines on the passenger side as the return less rail points straight back towards the firewall pretty close to the the engine centreline but more because the master/booster is on the drivers side and those lines will run down the drivers side.

[nsb29]

why not run your line on the out side of the frame that will keep it away from your exhaust I have ben wondering im using a corvette fuel filter w/belt in regular can I put it by the tank so I only run one line up to the fuel rail ??

[MalibuSSwagon]

I mostly wrapped the lines as it does pass fairly close to the exhaust as it heads up the firewall, and it's nylon line. Likely overkill but it was cheap insurance.

[BR3W CITY]

Originally Posted by clemsonteg

t IF something went wrong and the line became cut or punctured it could spray pressurized fuel on hot exhaust.

Any reason why you picked the passenger side over the driver side?

Mine pumped fuel onto the headers and it didn't ignite. Heat and open flame will ignite things differently (think spark plug vs compression ignition). Its possible, I suppose. I chose the passenger side because my brake stuff all runs the driver side and I wanted space for a chute cable and other stuff on that side.

Originally Posted by Ole Greenie

The fuel supply line came off! It had unhooked itself from the fuel rail and was hanging on by 1/2".

This is a unfortunately common problem with old-design Quick-connect fittings, as the only thing retaining the fitting is the "clip" on the inside. If you re-used stock fittings, its worth buying a new internal clip because they fatigue very quicky (especially when being removed without a quick disconnect tool). The Earls and Holley fittings that used the old-style connection fail in the same manner, if not worse. The best option is a quick connect fitting with a positive retention (like the screw-on endplate the new fittings have, or like the ones you posted in the link).

Originally Posted by nsb29

why not run your line on the out side of the frame that will keep it away from your exhaust I have ben wondering im using a corvette fuel filter w/belt in regular can I put it by the tank so I only run one line up to the fuel rail ??

Since the frame is a channel, most folks run it inside so its out of the way. On the outside of the rail, you'd have a fairly visible set of lines and a filter. Mechanically thats fine, just not really visually appealing.

[clemsonteg]

I'll have to see how much clearance I have between the inside of the frame and my exhaust. My rear brake line runs down the passenger side, along with my current fuel line. I can see how things could become crowded by the time I add in a supply, return, and fuel pump wiring.

[Wasted Income]

I would do a stainless or aluminum hard line in the areas where it gets close to the exhaust.

I ran my feed on the driver side, and return on the passenger side, all hard line, with braided hose at the connections.

[michael bustamante]

wasted income? what is the k&n cylinder on the passenger frame rail?

[JJH Jimmy]

I ran mine with hard SS line down the drivers side frame rail and used Russell Proclassic hose from the frame rail to the engine. I built heat shields and welded them to the exhaust. I also bought Thermo Tec adhesive insulation and stuck a couple of layers on top of the heat shields. I used this same method for my transmission lines as well.

[Wasted Income]

Originally Posted by michael bustamante

wasted income? what is the k&n cylinder on the passenger frame rail?

It's a 25 micron filter. I've also got a 100 micron filter between the tank and the pump.

[SierraMtns]

Originally Posted by Wasted Income

I would do a stainless or aluminum hard line in the areas where it gets close to the exhaust.

I ran my feed on the driver side, and return on the passenger side, all hard line, with braided hose at the connections.

Do you think it would be ok to run the exhaust down a long the fuel lines? I am running hard lines like yours down the frame thats boxed so the exhaust pipes will be 1.5-2" away from the fuel line going down the frame. Everything is getting really close together the more I build my truck.