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914World.com _ 914World Garage _ Fuel line Question

Posted by: kfish914 Jun 3 2010, 09:32 AM

I know I may get a lashing for asking this but with a budget in mind. Would there be any issues with replacing the hard plastic lines with rubber lines? I know I could use electrician's fish tape to pull it through into place. My worries are the grommet area (where the hose would pass through the body panels) rubbing or kinking the fuel line. I am exchanging the current 1.8 four, for a 2.7 six.
Any thoughts?

Posted by: drgchapman Jun 3 2010, 09:35 AM

Racer Chris' SS fuel lines.
Otherwise you may go up in flames.

Posted by: kfish914 Jun 3 2010, 09:46 AM

That is a BIG concern of mine. I like my steaks fire grilled but not me

Posted by: tradisrad Jun 3 2010, 10:04 AM

you mention budget, but you are putting in a big engine that I am sure cost big $$$. Don't skimp on the last $100.
I've got Racer Chris' SS line, but you could fashion some of your own SS lines and save a few $$$.
How much is high pressure fuel hose going to cost? $5 a foot or more? how many feet? that will add up quickly.

Posted by: RobW Jun 3 2010, 10:19 AM

agree.gif

Just go buy the friggin lines! They are pre bent and fit right in....

What's piece of mind worth?

Posted by: PRS914-6 Jun 3 2010, 10:32 AM

I used high quality German fuel injection line the entire length. I installed heat shrink over the inside portion for abrasion protection and insulation over the outside portions for heat protection. All penetrations have rubber grommets. The advantage is the reduction in joints. Not legal for some racing.

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Posted by: SLITS Jun 3 2010, 10:37 AM

Jeeeze .... steel line, SS line .... whatever. I buy a 10' section, cut and bend it myself with a cheap Harbor Freight Tubing Bender.

I won't run rubber or stainless braid where I can't visually inspect it.

In lieu of that, I will use the black plastic line out of a '75 - '76 model ... much like the high pressure CIS line.

Posted by: SLITS Jun 3 2010, 10:37 AM

Jeeeze .... steel line, SS line .... whatever. I buy a 10' section, cut and bend it myself with a cheap Harbor Freight Tubing Bender.

I won't run rubber or stainless braid where I can't visually inspect it.

In lieu of that, I will use the black plastic line out of a '75 - '76 model ... much like the high pressure CIS line.

Posted by: realred914 Jun 3 2010, 12:16 PM

QUOTE(PRS914-6 @ Jun 3 2010, 09:32 AM) *

I used high quality German fuel injection line the entire length. I installed heat shrink over the inside portion for abrasion protection and insulation over the outside portions for heat protection. All penetrations have rubber grommets. The advantage is the reduction in joints. Not legal for some racing.

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that hose is probably not rated SAE 30R9 which means it is not lined and is not resistant to the new formula oxgenated fuels. if you use oxegenated fuel, that hose will degrade internally. the 30R9 hose has a teflon like inner liner to resist the new fuels, it is now the standard FI rated hose required in california tests.


for teh tunnel lines, on a budget, i'd replace with plastic hard lines they make them fuel proof, and there are cheap.

remeber todays gasoline is not like yesterdays gas. the new stuff is corrosive to metals unlike before,a dn will eat up many of the common rubber parts used in teh past, be it hoses, pump diaphrams, and carborater seals.

the use of SAE30R9 is highly recommended so you dont have fuel hose failure do to breakdown cause of the new fuels.

Posted by: AvalonFal Jun 3 2010, 02:22 PM

I posted this pic a few years back on a similar thread. This is the fuel hose damage I found when I removed the fuel tank from a '74 I had just bought. The writing on the hose says "NOT FOR USE WITH UNLEADED OR GASOHOL FUELS".

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Paul






Posted by: underthetire Jun 3 2010, 03:12 PM

Really, i mean by the time you buy enough FI hose to do the job, you could buy steel lines, dinner, a movie or a hooker a female companion for the night.

Posted by: ME733 Jun 3 2010, 03:26 PM

.....Any fuel line that cannot be visably inspected should be STEEL/stainless steel., ....grommits to soft mount thru body., adel clamps to mount in the tunnel, or engine bay, as necessary....

Posted by: PRS914-6 Jun 3 2010, 05:10 PM

QUOTE(underthetire @ Jun 3 2010, 02:12 PM) *

Really, i mean by the time you buy enough FI hose to do the job, you could buy steel lines, dinner, a movie or a hooker a female companion for the night.


Really? $98.00 for a pair of SS lines. For High pressure systems add fittings at $48.00 and you get $146.00 to save purchasing an extra 5 feet of fuel line. The cost of 5 feet of extra fuel line going through the tunnel wouldn't get you a hand job with even the cheapest hooker. lol-2.gif

In addition, the flares on the metal lines leave something to be desired for a high pressure system and puts a joint between that flare and rubber both front and rear (X2) and in the hottest part of the car where a failure would blow fuel all over hot headers and engine. That would concern me a lot more than a one piece fuel line running front to rear but runs through the tunnel.

Many cars have hidden rubber fuel line. Look at many cars on the top of the fuel tank. If you work on cars, most leaks show up at the joints, especially at the clamps.

So you have a choices...

1. Replace the lines with a one piece FI line and live with a line through the cab
2. Use metal through the cab and live with twice the connections

It's all about your comfort level......

Probably the best compromise is steel lines with FI fittings silver soldered on the ends so that a mechanical connection can be made but that makes getting them through the chassis difficult.

Posted by: Cap'n Krusty Jun 3 2010, 05:17 PM

QUOTE(PRS914-6 @ Jun 3 2010, 04:10 PM) *

QUOTE(underthetire @ Jun 3 2010, 02:12 PM) *

Really, i mean by the time you buy enough FI hose to do the job, you could buy steel lines, dinner, a movie or a hooker a female companion for the night.


Really? $98.00 for a pair of SS lines. For High pressure systems add fittings at $48.00 and you get $146.00 to save purchasing an extra 5 feet of fuel line. The cost of 5 feet of extra fuel line going through the tunnel wouldn't get you a hand job with even the cheapest hooker. lol-2.gif

In addition, the flares on the metal lines leave something to be desired for a high pressure system and puts a joint between that flare and rubber both front and rear (X2) and in the hottest part of the car where a failure would blow fuel all over hot headers and engine. That would concern me a lot more than a one piece fuel line running front to rear but runs through the tunnel.

Many cars have hidden rubber fuel line. Look at many cars on the top of the fuel tank. If you work on cars, most leaks show up at the joints, especially at the clamps.

So you have a choices...

1. Replace the lines with a one piece FI line and live with a line through the cab
2. Use metal through the cab and live with twice the connections

It's all about your comfort level......

Probably the best compromise is steel lines with FI fittings silver soldered on the ends so that a mechanical connection can be made but that makes getting them through the chassis difficult.


I change those hoses on top of the tank all the time, often on cars that are 5-6 years old. I would NEVER run rubber fuel line down the tunnel.

The Cap'n

Posted by: tod914 Jun 3 2010, 06:19 PM

If you want to do it inexpensively and have piece of mind, you can goto your flaps and pick up a 60" length of flexable steel brake line and use a pipe cutter to take off the ends. File it down and flare it if you want. The 60" length works perfect. You'll need to bend/arc the lines abit inside the gas tank area with a tube bender. Easy enough to do once you run the lines through the tunnel. The line should be $5.00 each or so.

Posted by: iamchappy Jun 3 2010, 07:35 PM

I have used Aeroquip Blue line, and SS braided line down the tunnel never felt comfortable with either.
I have Chris's - Tangerine SS solid lines with AN fittings, i dont even think about it any more. As far as i am concerned the SS lines are really the only way to go, you will never need to replace them ever!

Posted by: bandjoey Jun 3 2010, 08:06 PM

I thought Clay did a write up on install metal fuel lines on a budget...can't find it now. Search or does someone knows where it is??

Posted by: 9146986 Jun 3 2010, 08:19 PM

You need to put a bubble flare on the end of the tubing, or use a die and cut threads on the OD of the tubing, otherwise it can push off. Stainless is so smooth you can tighten a hose clamp on there as tight as possible and still pull the hose off.

Racer Chris' solution is to tack weld a ferrule on the tubing.

Posted by: kfish914 Jun 4 2010, 07:56 AM

Thanks guys for all your responses. Yeah i know I am putting in a 2.7 but I bought it off a local guy in the nieghborhood who did a 3.2 conversion on his 911 and his wife wanted the engine out of the garage. I happen to be at the right place at the right time and picked it up for $1800. I know you are all thinking it needed a lot of help, but really i had heard it run the summer before and it sounded good. I did take it down and rebuild it just to make sure. It was pretty clean besides one cyclinder. Yes I was going to run one line from the tank to the back and then one line for the return less connections to leak. I am able to pick up the new updated fuel lines at a local NAPA store for 1.59 per foot. My worries were that it running along the tunnel and across a lot of metal "edges" that it would cause cuts into the line and POOF flames everywhere. Thanks for all your input. I knew that I was setting myself up for a lashing but I also knew that you guys wouldn't let me down with some great ideas and advice.

Posted by: Nürburg Nomad Jun 4 2010, 10:23 AM

Sounds like there's a bunch of fuel system experts in here! Who wants to consult on my thread?! biggrin.gif Pretty please?

http://www.914world.com/bbs2/index.php?showtopic=107611

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