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Discussion Starter · #1 ·
is there a special type of rubber/silicone fuel line I should use? Can I use rubber the entire length? Is there recommended sizes for pickup and return lines?

engine is 92 6 cyl cummins. I think i have a restriction with the factory jeep lines?

Thanks

Joe
 

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What Scott said, plus I used a short length of clear tubing, diesel rated, right before the lift pump. That way I can check for supply intergrity or bubbles at a glance. Can potentially save some grief.
 

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Discussion Starter · #4 ·
I saw some nice looking 3/8's hose at ACE that has an appearance of silicone/poly instead of regular rubber fuel hose. It says fuel line, but doesnt actually say whether its diesel rated or not.
 

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SAE 30R7 is rated for regular diesel (should be printed on the side of the hose). Biodiesel? That's a whole 'nother ballgame. No one really has long term info but besides the viton stuff SAE 30R9 is rated for alternative fuels. I got some at NAPA but they only come in 10ft lengths and is $7 a foot! Not cheap stuff. B20 won't do much but if you run B100 it's a good idea to check the hoses for degredation.
 

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First off, the factory first gen dodges have just 5/16" plastic supply lines and run fine. No restriction. I doubt your jeep fuel lines are a restriction!!! All of our 6BT 5.9 liter and 6CT Cummins 8.3 liter equipment at work is 3/8" supply....nothing is larger. They make rated power all day long.

I can't see one reason at all for going over 5/16" or 3/8" unless you live in Alaska and need to move gelled fuel through the lines.

Return is same size and the line coming off of the engine: 3/16"

No one really has long term info but besides the viton stuff SAE 30R9 is rated for alternative fuels. I got some at NAPA but they only come in 10ft lengths and is $7 a foot!
The "EFI rated" fuel hose at Napa is $2 a foot and is Viton. It isn't black, it is almost a really dark green color.
 

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Discussion Starter · #7 ·
The factory return line on jeep is smaller than the supply line. would that cause any loss of power.
 

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The factory return line on jeep is smaller than the supply line. would that cause any loss of power.
No, of course not. The return works the hardest at idle since the engine isn't using much fuel to run (returns most to the tank)

At full power the return will not be retuning much fuel, the engine will be using it.

a 3/16" return works fine
 

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First off, the factory first gen dodges have just 5/16" plastic supply lines and run fine. No restriction. I doubt your jeep fuel lines are a restriction!!! All of our 6BT 5.9 liter and 6CT Cummins 8.3 liter equipment at work is 3/8" supply....nothing is larger. They make rated power all day long.

I can't see one reason at all for going over 5/16" or 3/8" unless you live in Alaska and need to move gelled fuel through the lines.

Return is same size and the line coming off of the engine: 3/16"



The "EFI rated" fuel hose at Napa is $2 a foot and is Viton. It isn't black, it is almost a really dark green color.
When I said 5/16 return is because the fuel tank that use a return have 5/16 not the 3/16.Can be done both way's .The bigger fuel isn't going to hurt anything .

Just my .02.

Scott
 

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I ended up deciding to run all new lines for our Durango. I was going to use the factory lines, but wondered how diesel would affect them. Well, I say lineS, but there is only a feed line...'00 Durango's don't have a return. Since I have to run a return anyway, I decided to run a new feed. I'll probably go with 5/16" just because its a bit easier to bend up in tight areas than 3/8". I'm using a 1/4" return. Hey, I bend lines every day...spending another 1/2 hour to run new lines isn't an issue (up here, steel lines have to be replaced every couple years because of rust...we are at the point of replacing lines on '02, '03, and '04 vehicles because of rust) and I'm going to use coated lines so maybe I'll get 3 years out of them. Thats longer than the Durango will last before it rusts out, so they will be fine.

Jim
 

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By the way, for general information: the clear fuel line that I use came from the hardware store! Checked all auto parts places, NAPA, Carquest, Kragen/Schucks etc and nobody could suggest a clear diesel fuel injection line. So I went to an Ace hardware and they have various plastic line on reels in a display.

A woman who knew nothing about diesels [I didn't care, she was a knock out] helped me, and says, "What about this one?" It was the cheapest garden variety stuff, not hi-tech, but on the reel it said 'Fuel line' as a possible use. I think it's normal polyethylene. It's been on for 6 months, no problems whatsover.

Some rubber hi-pressure fuel injection line I got was deteriorating in 1 week! Check the stuff out at your local hardware and read the specs, it's about $.79 a foot hah! Now I can SEE wha my fuel is doing!
 

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After endless problems with rubber based based fuel lines I did what all the trucks use in the UK and put clear nylon fuel line on ( black is no longer available, so the excise duty people can easily check for red diesel) , its been on about 5 or 6 years now and its still as good as new, and any bubbles can be seen to spot problems ( I easily tracked down a faulty electric fuel pump that was sucking in air when I had a chevy diesel in) All ends are brass compression fittings, easy to do and easy to alter also different size inlets and outlets are not a problem. Do the trucks in the US not use nylon or do they use rubber/synthetic type stuff? with worm drive clips . The nylon stuff really is fit & forget, it'll probably out live my truck. I have left a sample in biodiesel for a few years in a jar and it was unchanged. What is the deal with wanting rubber based fuel lines or even the synthetic stuff? The nylon is cheap, easy to fit, extremely hard wearing and available at all diesel shops (at least in the UK) and being clear helps pin point air bubbles. Also unaffected by salt so wont need changing every 3 or 4 years like steel lines. If its good enough for all the commercial vehicles in the UK its good enough for me. JMO

Gaza
 

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I know Biodiesel wasn't initially mentioned but if you are running fuel lines and want to run bio in the future it might be a good idea to run compatible stuff in the first place. I got these off a couple biodiesel sites.

Non Compatible Materials (B100)
Elastomers:
Nitrile Rubber
Polypropylene
Polyvinyl
Tygon
Behavior: Elastomers not compliant may degrade, soften, swell or seep from connections. Typically this only becomes an issue in vehicles built before 1993, which have older rubber hoses.
Metals:
Brass
Bronze
Copper
Lead
Tin
Zinc
Behavior: These metals can accelerate oxidation of the fuel and create insoluble gels and sediments when exposed to Biodiesel and air.
Paints: Most oil-based non enamel paint will be degraded by Biodiesel. Spills should be cleaned immediately with soap and water.

Compatible Materials (B100):
Elastomers:
Teflon
Viton
Fluorinated Plastic (i.e., Fluorinated Polyethylene, Fluorinated Polypropylene)
Nylon
Polyethylene (HDPE)
Silicone
Behavior: These materials can be used to transmit and store Biodiesel, this includes “red plastic” gasoline cans, polyethylene barrels and large plastic totes.
Metals:
Aluminum
Steel

Compatibility with B20:
No negative effects have been observed for elastomers and metals exposed to B20, which are compliant with petroleum diesel to begin with. Materials compatible with regular diesel should perform the same when used with B20.
 

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The nylon line sounds good. Do you know what temps this stuff works at? I'm not as concerned with heat as I am with cold. It gets to -30 on a regular basis in the winter, and can be colder than that. I've had to replace factory plastic lines on several vehicles because they got brittle and cracked in the cold. We ended up running coated metal line where possible, and high PSI rated hose where necessary for flexibility. Also, do you have any pictures, or other details to help me get the right stuff? We have a couple hardware stores in town, but nobody knows anything about diesels. I asked the local part's stores about diesel rated fuel line, and they looked at me funny and offered me standard fuel line, with no knowledge whether it was diesel rated.

Jim
 

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I have been trying to google some info.... I am just cutting and pasting random info here!

Apparently, plain ol' fuel line is SAE 30R7 (cheap $2 a foot junk)


http://www.dieseltruckresource.com/dev/archive/index.php/t-89044.html


EFI rated fuel hose is SAE 30R9
(definitely handles diesel according to the specifications)

"Fuel injection (SAE 30R9) hose is reinforced to handle higher pressures up to 180 psi. It can be used on all injection systems that use hose clamps.
Fuel injection hose is designed for low permeation contact with a wide variety of alcohols, alcohol fuel blends, and diesel fuel. Gates SAE 30R9 hose uses a laminated tube of Fluoro-elastomer.
SAE30R9 hose is also recommended for diesel fuel because its fluoroelastomer tube resists deterioration caused by some diesel fuel additives."

Napa H201 1/4"
Napa H202 5/16"
Napa H203 3/8"
Napa H204 1/4"
Napa H205 5/16"


http://www.gates.com/index.cfm?location_id=541
http://www.gates.com/brochure.cfm?brochure=5091&location_id=541

High pressure (EFI) hose that needs to be submersed in tanks is SAE 30R10 ($17 a foot!) Fluoroelastomer (FKM) tubed cover resists gas and fuel permeation and retards ageing

Also handles diesel fine....has same inner material but tougher outer rubber. Working pressure 180 PSI

Napa H213 - 3/8" SAE 30R10 rated hose (Gates number 27097)
Napa H206 - 3/8" SAE 30R10 rated hose ($5.80 / ft)
Napa H209 - 5/16" SAE 30R10 rated hose
Napa H210 - 1/4" 30R10 rated hose


http://www.gates.com/common/downloads/files/gates/brochure/techtipsform.pdf

"Finally, for submersible applications such as on the in-tank fuel pump, only SAE30R10 hose should be used, because when the hose fails, the pump will fail. Hose construction consists of low swell fluoroelastomer compounds in the tube and cover that resist gasoline and diesel fuel permeation and aging. Standard hoses have these fuel-resistant characteristics in the tube portion only. Contact your Gates jobber for information on Gates MPI/fuel injection hose and submersible fuel line hose."


I needed some replacement 5/8" fuel line for the vent side of my filler neck, and it is Napa H200
 

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The nylon line sounds good. Do you know what temps this stuff works at? I'm not as concerned with heat as I am with cold. It gets to -30 on a regular basis in the winter, and can be colder than that. I've had to replace factory plastic lines on several vehicles because they got brittle and cracked in the cold. We ended up running coated metal line where possible, and high PSI rated hose where necessary for flexibility. Also, do you have any pictures, or other details to help me get the right stuff? We have a couple hardware stores in town, but nobody knows anything about diesels. I asked the local part's stores about diesel rated fuel line, and they looked at me funny and offered me standard fuel line, with no knowledge whether it was diesel rated.

Jim
Not sure about the min temp, but on a TV programme called Ice road truckers they use nylon line for the air brakes so it must be able to cope with the low temps. If you have done any household plumbing with copper pipes and compression fittings its virtually the same. You can get inserts to put in the end of the pipe so that it doesn't crush but these aren't compulsory if you don't overtighten. When I drove my first diesel I thought thats it no more petrol engines for me, well when I put nylon fuel lines on I had the same eureka moment and thought why doesn't everybody use nylon. Still not everyone is convinced about diesels. Some people stick with what they know.
You can get nylon tubing in many colours and sizes from a pneumatics store, they also use push fit connectors which make the job very easy. I used thes with a biodiesel filter system and never had a problem with them but they are more expensive.

Gaza
 

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As posted above, polyethylene is compatible with bio, diesel, and verg. Bonus points: IT'S THE CHEAPEST LINE YOU'LL FIND! I got the most common hardware store stuff and it's as good as any, sometimes less than 50 cents a foot.

Only place I use it is before the lift pump, at end of tank feed line. Eveything else is steel. An 8"-10" section lets you check line integrity for bubbles at a glance.

Shop around on clamps. There's a type that has a wider band which overlaps itself, and then the worm drive screw assembly is on outside of clamping area, so it [and those little cut out holes] doesn't dig into fuel line. These are commonly available as hi-pressure fuel injection line clamps. About twice the price but the junk is junk so these are a good solution.

Brass fittings: there's so little brass exposure in a fitting that it has almost no effect on fuel, but of course brass fuel lines would be a disaster. From what I read stainless or aluminum lines are best, in that order of preference, with steel third and copper a no-no. Steel usually works okay for a long time even though it's not first choice.
 

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Could you please enlighten me about special "diesel-rated" fuel line? If have always used regular fuel line without issues. I even know of an old-timer that used red air hose without issue for more than 15 years. Of course, this was with #1 diesel, #2 diesel and Jet-A. I haven't used biodiesel or vegetable oil yet. Are you referring to Aeroquip-type hose with a rubber or neoprene inside?
 

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Could you please enlighten me about special "diesel-rated" fuel line?
Well, just because someone else got lucky with the right stuff 15 years ago doesn't mean it'll work with what is coming out of the fuel pumps today. There is tons of info in this thread already, what more could you possibly want to know? The list of compatible and non-compatible is on the first page.
 
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