Fuel Line Fitting: Hairpin or Duck Bill Clip? (’85 F-150 EFI 5l dual tanks)

[Gary Lewis]

Ok, here's what I know about doing the fuel lines. In another post I'll look for part numbers and discuss regulators and Schrader valves.

Yes, the supply is 3/8" and the return is 5/16". However, Dorman sells a roll of 3/8" Nylon line that is just long enough to do the whole truck, both supply and return

Music to my ears! Question: (the Devil is in the details!): Does this apply to a long bed???

(Note: If not, I've heard that Nylon can stretch )

Anyway, there was this post:

"Rusty S85 Aug 6, 2021 10:53am

should be 5/16" hardline.

That is what is on my truck is 5/16" line from tank to carb.  Going to be replaced with 3/8" hardline as 5/16" is too small for high volume high pressure EFI pump.  For a carb 5/16" would be fine for a stock or fairly stock engine....."

url reference: http://forum.garysgaragemahal.com/Fuel-Line-Fix-td101554.html

(Note: I don't know how to cross-thread quote something)

So, going all 3/8", round trip, wouldn't hurt and might even be helpful.

Question: What does anyone know about the clips that hold the tubes/lines to the rail? would gong all 3/8" create a size problem?

That's what I did and there are NO leaks. It went together very nicely and actually pretty easily.

Gary - this sounds VERY encouraging!

With all this information I think I'm game to do the connectors myself.

Question: On your project, did you put the foam cover on the lines (like is shown in my pictures)?

If no one has done it, I'd be willing to make a How-To video about making up the connectors on the Nylon lines.

Thanks a bunch for all the helpful URLs.

The clips that hold the lines to the rails have an internal spring that has to be pushed out of the way. You use a tool to do that, and I think this is the set I bought.

And the roll of Nylon tubing did Big Blue, which is a regular cab long bed.

As for foam, no. But my lines had a rubber hose over them in some places and I put that back and used some space age insulation on them where they got close to the exhaust, as shown below:

And we don't have a video, so go for it!

[Nemesis F150]

As for the regulator, it is on the back of the fuel delivery manifold and is base part # 9C968.

If the regulator has a "rubber" hose attached to the top, then I'm pretty sure that is what it is at the rear of the engine. Not with the greatest accessibility.

 

[ArdWrknTrk]

As for the regulator, it is on the back of the fuel delivery manifold and is base part # 9C968.

If the regulator has a "rubber" hose attached to the top, then I'm pretty sure that is what it is at the rear of the engine. Not with the greatest accessibility.

The regulator relies on vacuum to adjust fuel pressure depending on engine load.

With an open throttle vacuum drops and the fuel pressure goes up.

With the throttle closed vacuum is high and the regulator returns a greater percentage of fuel to the tank.

If you find the vacuum line wet or full of fumes the regulator is failing and should be replaced.

[Nemesis F150]

With an open throttle vacuum drops and the fuel pressure goes up.

And, in the old days, the windshield wipers would slow down when stepping on the gas.

Electric windshield wipers are nicer.

If you find the vacuum line wet or full of fumes the regulator is failing and should be replaced.

Very good to know!

Thank you for this important bit of extra information.

[ArdWrknTrk]

With an open throttle vacuum drops and the fuel pressure goes up.

And, in the old days, the windshield wipers would slow down when stepping on the gas.

Electric windshield wipers are nicer.

If you find the vacuum line wet or full of fumes the regulator is failing and should be replaced.

Very good to know!

Thank you for this important bit of extra information.

With these trucks if the vacuum reservoir isn't up to snuff or there are other leaks the climate controls will default to defrost.

I'm assuming Ford made defrost the default position because being able to see is more important than comfort.

I remember when Beetles had the washer bottle connected to the spare tire for pressure, but that's as far back as I go.

 

[Nemesis F150]

The clips that hold the lines to the rails have an internal spring that has to be pushed out of the way. You use a tool to do that, ...

More tools for the tool box!

Thanks for the heads-up and the link!

And the roll of Nylon tubing did Big Blue, which is a regular cab long bed.

Perfect! (so long as I don't make a mistake in cutting or measuring)

As for foam, no. But my lines had a rubber hose over them in some places and I put that back and used some space age insulation on them where they got close to the exhaust, as shown below:

I'll have to look again at the tubing covers, maybe they are hose instead of foam.

And, for the underside picture of your rig ... that is sooo OUTSTANDING! I'd nominate it for "Picture of the Month"!

This is so clean that at a truck show you'll have to put a mirror under it with lights and the rig on jack stands. Gorgeous!

Under the heading "a picture is worth a thousand words", the fuel line covers with the tubing and the insulation really helps to show how to do it. I plan to follow in your footsteps.

By the way, noticed a Ford manufacturing plate on the far right side ... what is that for? I don't recall ever seeing one.

[Nemesis F150]

With these trucks if the vacuum reservoir isn't up to snuff or there are other leaks the climate controls will default to defrost.

I'm assuming Ford made defrost the default position because being able to see is more important than comfort.

That's a good one!

I remember when Beetles had the washer bottle connected to the spare tire for pressure, but that's as far back as I go.

Guess I missed that one ... was in the service during Viet Nam so basically was isolated from nearly all civilian news. However, once out and back in college, I have to say the mini-skirts were really super!

Story: Was finally early to one of my liberal arts classes, last day with the course Final, (normally late due to a long walk from a previous class) and noticed all the guys standing around the entrance to the stair well that went upstairs. Looking up I could see why ....

[Gary Lewis]

The clips that hold the lines to the rails have an internal spring that has to be pushed out of the way. You use a tool to do that, ...

More tools for the tool box!

Thanks for the heads-up and the link!

And the roll of Nylon tubing did Big Blue, which is a regular cab long bed.

Perfect! (so long as I don't make a mistake in cutting or measuring)

As for foam, no. But my lines had a rubber hose over them in some places and I put that back and used some space age insulation on them where they got close to the exhaust, as shown below:

I'll have to look again at the tubing covers, maybe they are hose instead of foam.

And, for the underside picture of your rig ... that is sooo OUTSTANDING! I'd nominate it for "Picture of the Month"!

This is so clean that at a truck show you'll have to put a mirror under it with lights and the rig on jack stands. Gorgeous!

Under the heading "a picture is worth a thousand words", the fuel line covers with the tubing and the insulation really helps to show how to do it. I plan to follow in your footsteps.

By the way, noticed a Ford manufacturing plate on the far right side ... what is that for? I don't recall ever seeing one.

The plate is on the ZF5 tranny. That tranny came from a later F350 truck and I used it to replace the T-19 for two reasons: it has an overdrive and it has a steeper first gear.

As for the underside of my truck, that's the way it was before I started using it. Now it has been on several hundred miles of dirt roads, many of them in the rain, and it isn't as clean.

Anyway, if you want to see what I did you can start here in my rather lengthy (281 pages and still going) thread on the transformation of Big Blue. Not every post from that point was about the fuel system, but you can skip over the others.

[Gary Lewis]

With these trucks if the vacuum reservoir isn't up to snuff or there are other leaks the climate controls will default to defrost.

I'm assuming Ford made defrost the default position because being able to see is more important than comfort.

That's a good one!

I remember when Beetles had the washer bottle connected to the spare tire for pressure, but that's as far back as I go.

Guess I missed that one ... was in the service during Viet Nam so basically was isolated from nearly all civilian news. However, once out and back in college, I have to say the mini-skirts were really super!

Story: Was finally early to one of my liberal arts classes, last day with the course Final, (normally late due to a long walk from a previous class) and noticed all the guys standing around the entrance to the stair well that went upstairs. Looking up I could see why ....

If you were in Viet Nam you may be a contemporary of mine. I was lucky enough not to have to go as my birthday was #366 in the draft, but many of my friends did go. Born in '47.

[myrl883]

I've never seen duckbill clips on trucks. I believe they were only used on vapor recovery lines on compact and midsize cars. White hairpins on 5/16" lines, black on 3/8".