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Fri Dec 16, 2005 5:25 pm

I removed the metal line that passed trhu the tunnel for the fuel and want to replace it with a single flexible line from the fuel tank petcock to the carb.

What would you suggest?
A regular black rubber fuel hose or a copper tubbing line? Why?

thanks!

Fri Dec 16, 2005 5:29 pm

Do not use copper unless you want a leak and then a fire. Go with Stainless Steel and located in an area that if you hit a rock or something it is protected to prevent it from getting smashed.

Fri Dec 16, 2005 5:59 pm

A long piece of rubber hose can collapse. Copper should NEVER be used as a fuel line- its too soft, and can potentially have pinhole leaks-esp near bends.
Stick with steel, or if you want to upgrade, go stainless. VW used steel for a reason- its tough, SAFE, and longlasting.
:roll:

Fri Dec 16, 2005 6:11 pm

Where would I find a stainless steel line that thin or of any kind?

Fri Dec 16, 2005 6:19 pm

How about a stainless brake line? Would that work even though it would not be flexible??

Fri Dec 16, 2005 6:19 pm

alexh wrote: Where would I find a stainless steel line that thin or of any kind?

All of the hose specialty stores should have it.These stores usually supply hydralic hose & fittings for industrial use . in socal try hose man or air hose source. if not in socal check the phone book.

Fri Dec 16, 2005 7:38 pm

I could go with the stainless braided hose but its super expensive!

Remember I paid 80$ for a 1 foot section with two swaged ends for my boat's trim system, this was at the local hydraulics place.

Why would a regular rubber fuel hose collapse?

Fri Dec 16, 2005 8:00 pm

another option is aluminum... http://www.aircooled.net/new-bin/viewproductdetail.php?keyword2=THH0009&cartid=1216200534088212

Fri Dec 16, 2005 11:04 pm

The closet thing to the stock 5mm steel line is a #4 (1/4") hard line. Stainless steel is the toughest, but it hard to bend. If use a slip fitting on either end like the stock setup you can get it in with some work, and generally available benders. Aluminum is much softer and easier to work, but will wear through if you let it rub any where. Stainless would be my choice.

The flexible line come in three different materials. A fiber reinforced rubber, a braided stainless neoprene, and a stainless covered Teflon. The Teflon hose is what is used for brake system, but it will not stand up to any kind of suction. Since the tank side of fuel system is suction, you should out a neoprene based product. However, neoprene is not a 'forever' product like the stainless hard line.

Another thing about hard line. All AN fittings are manufactured on a 37.5 degree flare standard, unlike standard automotive fittings which are 45 degree. When working with softer material like aluminium, brass or copper it is possible to use automotive 45 degree flaring tools, but with stainless it's a must to buy an aircraft grade 37.5 degree flare tool. If you don't use the right tool on stainless it will leak. Also, stainless hard line only comes in straight 20 foot lengths, so find a local supplier and have them cut you a short piece of stock.

Hope that helps,
Alan

Fri Dec 16, 2005 11:07 pm

alexh wrote: want to replace it with a single flexible line from the fuel tank petcock to the carb. What would you suggest?
A regular black rubber fuel hose or a copper tubbing line? Why? thanks!
What's a fuel tank petcock?

Sat Dec 17, 2005 12:07 am

HBRag wrote:

Another thing about hard line. All AN fittings are manufactured on a 37.5 degree flare standard, unlike standard automotive fittings which are 45 degree.

there are also jic fittings that are very similar to an but are not interchangable.i have seen these on heavey equipment but it shouldn't be a problem , jic fittings are labled as such engraved on the fitting.

AN FITTINGS
The Tube Fittings Division receives numerous inquiries regarding "AN" fittings. AN (Air Force - Navy Aeronautical
Standard) and AND (Air Force - Navy Aeronautical Design Standard) are standards used by the U.S. Military in
aviation applications. AN fittings are manufactured to meet above standards. These fittings include the 37° flare,
flareless, hose connections, "banjo" type fittings, specialized flange fittings, pipe fittings and other types of
connections. This bulletin has been developed to answer frequently asked questions about the 37° flare AN fittings
and how they relate to their industrial counterpart, the SAE (Society of Automotive Engineers) 37° flare (Triple-Lok)
fittings.
History
Parker pioneered the flare fitting technology in the 1920's with the introduction of the inverted flare fitting flollowed
by the Parker Triple Fitting in early 1930's. They were adopted by Air Corps (a part of the U.S. Army at that time)
as AC-810 and AC-811. As the operating pressures increased, inverted flare did not perform as well as Triple
Fitting, and its use started declining. The ease of manufacture of Triple Fitting provided additional advantage that
resulted in quick acceptance of it in various industrial and military applications.
The Triple Fitting was a patented three-piece design similar to current Triple-Lok, except it had 30° flare angle
instead of the 37°. This fitting design was the forerunner of the current AN and SAE 37° flare fittings.
Parker Hannifin Corporation – Tube Fittings Division
Evolution of the Flared Fitting
Fitting Solutions Series – No. 11
Parker Hannifin Corporation – Tube Fittings Division
3885 Gateway Blvd., Columbus, OH 43228 USA
Phone: (614) 279-7070 Fax: (614) 279-7685
The U.S. Air Force, with help from Wright Patterson Air Force base, developed a fitting with 37° flare angle, before
WWII, which became known as the "AN" fitting. This fitting had precision 3A/3B threads. The use of "AN" fittings
proliferated from the 1930's through the 1960's to include most branches of U.S. Military, Military Contractors,
General Aviation and Commercial Aviation. These fittings were even adopted for use in many land/sea applications
of the U.S. Military as well, leading to confusion between AN and its industrial counterpart, the SAE 37° fitting.
After the war, several versions of 37° flare fittings flooded the industrial market, creating a nightmare for the users.
The Joint Industry Conference (JIC), an organization of manufacturers, decided to standardize on the "AN" design,
except with 2A/2B thread class for ease in manufacturing. These fittings came to be known, throughout the world,
as "JIC" fittings. The JIC wanted the prestige of SAE for the fitting standard. They convinced SAE to take on the
task and helped in the development of the standard. Thus, the SAE standard 37° flare fitting became part of SAE
J514 in 1950. The fitting became an ISO standard, ISO 8434, in 1986, replaced by ISO 8434-2 in 1996.
AN Fittings Today
AN fittings remain prevalent today. However, the U.S. Military is canceling many of the true AN/AND standards and
replacing them with AS (Aerospace Standards) standards developed, again, by SAE. Many aircraft/aerospace
applications are moving towards aluminum and titanium for optimized weight-to-strength parameters.
Differences Between AN Flare & 37° Industrial Flare
There are several differences between "comparable" industrial 37° flare (SAE/ISO) and AN style fittings. Some
include:
Threads: AN37° Flare: Male & Female, Class 3A/3B UNJ/UNJF (radiused root threads)
SAE/ISO: Male & Female, Class 2A/2B, UN/UNF Series threads.
Reason: Tighter tolerances and better fatigue life for aircraft, aerospace, military
applications.
Military Conformance
Standards: AN Flare: AN flare fittings conform to MIL-F-5509 specifications
SAE: Some 37° flare fittings conform to MIL-F-18866 as shown on MS51500 through
MS5134
Industrial Conformance
Standards: AN Flare: Meet SAE Aerospace (AS) standards.
SAE/ISO: Meet the applicable dimensional & performance requirements of SAE J514/ISO
8434-2
Materials: AN Flare: Available commonly in, carbon steel, stainless steel (CRES), aluminum,
titanium and copper/nickel
SAE/ISO: Available in commonly carbon steel, stainless steel, and brass
General: In addition to the above noted differences, drop lengths, hex sizes, hex widths
may also vary between "comparable" AN flare and 37° industrial flare products
in some sizes.
Interchangeability: AN flare and 37° industrial flare function identically. In many cases they appear to
be functionally interchangeable, but they are not. What this means is that while
the products may look similar, one must not offer a Parker Triple-Lok fitting (or any
other industrial 37° flare design) as a direct substitution.
For cost and availability reasons. 37° Parker Triple-Lok fittings may be offered as alternatives to AN/AND flare
fittings only if:
1.) Customer approves substitution and
2.) Triple-Lok fittings are used for ground support/land/sea applications only.
Note: Parker Triple-Lok (or other TFD products) fittings are not for use in Aerospace, General Aviation,
Commercial Aviation or Military Aviation applications. When in doubt, contact Parker Tube Fittings
Division.
If a customer requires products manufactured to AN/AND specifications, TFD recommends calling Parker Hannifin
Corporation Stratoflex Aerospace/Military Division in Fort Worth, Texas at (817) 738-6543.
TFD sincerely appreciates the opportunity to better explain the often-misunderstood world of AN Fittings. Look for
another upcoming Fittings Solutions soon.

Sat Dec 17, 2005 5:58 am

Do not use a lone rubber hose or copper line.

Use a steel or even an aluminum line.

Sat Dec 17, 2005 8:24 am

use brake line and fuel tubing between the lines and it will be fine.

Sat Dec 17, 2005 8:58 am

Here is an alternative: http://www.paragonperformance.com/fuel%20line%20hose.html

Sat Dec 17, 2005 9:10 am

Some state inspections check the fuel line and might require a hardline running from front to back.

Sat Dec 17, 2005 1:59 pm

CJG wrote: use brake line and fuel tubing between the lines and it will be fine.

Isn't the ID of brake line about a third that of fuel line? Will it flow enough?

Sat Dec 17, 2005 2:01 pm

BirdLives wrote: CJG wrote: use brake line and fuel tubing between the lines and it will be fine.

Isn't the ID of brake line about a third that of fuel line? Will it flow enough?

Sure is... you want a 5.5mm (1/4") line.

Take a look at this:
http://store.summitracing.com/default.asp?Ntt=fuel...search.asp

Sun Dec 18, 2005 12:11 am

I purchased 3/8" stainless hard fuel line in a roll from Summit along with the correct 37.5 degree flaring tool for my project. They also sell steel and aluminum in sizes from 3/16" to 5/8" I believe. Tough to get it in the original location though without a lot of cutting and welding of the tunnel.

Sun Dec 18, 2005 1:25 am

I wouldn't worry about using stainless. The standard steel lines are good for decades. Think of how many people are still running their factory steel line. I doubt this car will be driven in the salt much, so corrosion isn't really a big factor. If your concerned, paint it with a quality paint.

As far as diameter is concerned, 1/4" fuel line, and 1/4" brake line are the same size tubing. the only difference is what the sticker says.

Also, on running one long flexable line. In the event that you ever race the car, most tracks only allow 1' total flexable(non braided) fuel line.