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Changing nylon fuel lines with braided lines writeup


Old 10-15-2009, 10:08 PM
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Default Changing nylon fuel lines with braided lines writeup

I will do my best to make this easy for you, once I had the parts I figured it out pretty quick

DISCLAIMER: You are working with gas, which is flammable so no smoking or other flames, and when you need to cut a braided line it will spark as you cut the metal so try to do that somewhere else

The purpose of this is to remove the stock nylon fuel lines and replace them with much stronger braided lines, this is necessary to avoid leaks when modifying the top end of the engine (billet fuel rails, SS M90 supercharger, intercooler, etc.)

Here is what you will need, I went to Summit Racing and got them:

1x RUS-640850 Fuel Rail Fitting, Aluminum, Blue, Straight, 3/8 in., -6 AN
Fuel rail connector (supply) (if you are still using stock fuel rails, most aftermarket will have -6 AN)

1x RUS-640863Fuel Rail Fitting, Aluminum, Black, Straight, 5/16 in., -6 AN,
Fuel rail connector (return) (if you are still using stock fuel rails, most aftermarket will have -6 AN)

1x EAR-165006ERL Fitting, -6 AN Male to 3/8 in. Tube, Aluminum, Red/Blue
Metal tube to straight hose end (supply)

1x EAR-165056ERL Fitting, -6 AN Male to 5/16 in. Tube, Aluminum, Red/Blue
Metal tube to straight hose end (return)

2x SUM-220687 Fitting, Hose End, 90 Degree, -6 AN Hose to Female -6 AN, Aluminum, Red/Blue Anodized
Hose fitting to fuel rail fitting

2x SUM-220690 Fitting, Hose End, Straight, -6 AN Hose to Female -6 AN, Aluminum, Red/Blue Anodized
Metal tube connector to hose fitting

1x SUM-230610 Hose, Braided Stainless Steel, -6 AN, 10 ft. Length

Here are the fuel rail connectors:

The blue one on the left is the 3/8, black is 5/16 (blue wasn't in stock)

These will go from the fuel rail connectors to one end of the new hose:

You will need two(2) of these, one for each connection (supply/return)

These will go from the other end of your new hose to the hard tube connection:

You will need two(2) of these, one for each connection (supply/return)

These will attach to the hard metal tube to the end of the hose with the straight connector:

You will need one 3/8 (right) and one 5/16 (left)

Last thing you need is the braided line, it is a ten foot length that you can cut for your needs:

Ok so here you are all stock (mine look different beacuse the supply is on the front and the FPR and return are on the back with a flexible line connecting the two beacuse of the SC):

Now you need to get those old nylon lines out of the way, but first we need to relieve the pressure in the lines, for the 00+ people you will need to pull relay #39 in the back relay center, not sure for the other people, but you need to remove the fuel pump relay. Now go and start the car, after a few seconds it will die, then try to start it again just to make sure the pressure is relieved. Leave the relay out until you are ready to check for leaks.

Now you can start removing the fuel lines from the rails, there will be 2 plastic tabs under each connector, remove them by squeezing the 2 tabs together with one hand while pulling the connector off with the other, the piece with the tabs will stay on the rails for now. (you might want to have a towel ready to catch any remaining gas in the lines) Go ahead and just set the lines out of the way:

If you are keeping your stock fuel rails follow step A if you are going to put ZZP billet rails or something similar on your car follow step B

A) Those plastic tabs that are still on the fuel rail need to come off so you can put new ones on that came with your EFI connectors, these right here:

To get them off the rail use a small flat-head screwdriver to push the tabs away from the lip of the fuel rail and remove, here is what you should see:

Now take the small plastic piece from your EFI connectors (similar to the ones you just removed) and slide it over the fuel rail end until it clicks into place (make sure you put the 3/8 on the larger one and the 5/16 on the smaller one):

Don't put the metal connector on just yet.

B) Since you are putting new fuel rails in you need to remove the old ones, they are held in by 4 10mm nuts (for L36 rails, L67 may be different). Once you remove all of them disconnect the vaccuum line from the FPR and gently pull up until you are free from the car, set the entire piece aside (there will still be some gas left in the rails).

Now follow the instructions that came with your new rails to connect them. (you might not need the EFI connectors beacuse many will have the threaded connectors already on them that will connect from the braided line)

Time to get those nasty nylon lines out of the car! It will make things easier if you take out the airbox, I am figuring you have a cold air intake if you are doing this so just get the box/cone/tubing/etc. out of the way for now. The nylon lines are heat shrunk over the metal tube so the only way to get them out of there is to cut the metal tube below that, you will need a small tubing cutter to fit into the small space:

When you break through the tube it will leak out some gas, soak it up as best you can then feel free to toss the nylon lines into the garbage and accept that they weren't made for people with the mod bug.

Ok so now you need to put the hard tube connectors you bought on. But those tubes could use a cleaning so take some steel wool and get the tube nice and smooth, you will be thankful that it won't leak later. There are 3 pieces in each one, in my case; a red female end, a copper collar, and a blue threaded piece. Start by seperating the blue and red piece, the copper collar will be inside the red piece, put the red female end on first but make sure you have the right size connector (3/8 is the larger one) then slide the copper collar over the tube, slide it farther than you think it needs to go on so things get nice and tight and not leak:

Then put the blue piece onto the tube until it stops and slide the red piece to it and get it hand tight. Using a box wrench and a socket (11/16 IIRC) hold the red piece still with the box wrench and use the socket with some extenders to tighten the whole assembly:

Get it good and tight so they will not leak later.:

Now you are ready to run the braided lines, it will be very difficult to slide the red collars onto the outside of the line if the end is very frayed. The best way to cut the braided line is to wrap the area you need to cut with tape, duct tape worked well for me, and cut the line using a rotary tool such as a dremel or large serated sheers, wire cutters will not work and only smash the line.

Now we need to get threaded connectors onto the end of the hose, the blue piece is threaded into the red one so seperate the two and making sure to get all the metal threads into the red collar slide it onto the hose until it stops, you will need to twist it to get it all the way on. The blue piece will go inside the rubber part of the hose and thread into the red collar.(make sure the red collar doesn't slide off the outside or it will leak):

The stright connectors are for where you put the connectors on the hard tube and the 90 degree angle connectors are for the rails. Whichever side you decide to do first needs to be connected to its final spot you can see how long you will need to make your braided line, try to route it the way you intend to so it will be the right length. (add a little extra to prevent stress on the line)

Once you cut the correct length add the other connector to the end you just cut, one straight and one 90 degree one per line:

Stock fuel rails: Remember that EFI connector you took the plastic piece out of to put on the fuel rail? Take the metal piece and screw it into the 90 degree connector, make sure you put the supply on the line you cut to fit for the supply. Get it good and tight so it won't leak. Then all you need to do is push that metal connector onto the fuel line until it clicks. Remember the supply, the bigger metal tube will go to the bigger EFI connector.

Aftermarket fuel rails: Connect the lines in the correct location for the supply/return.

Now do the same for the other line. Put it all together and make sure you check every connection to prevent leaks.

Now go and out your fuel pump relay back in but DO NOT start the car, it is best to have someone watching all the connections while you turn the key to ON, but remember don't start the car. Once you are sure there are no leaks go ahead and start the car, make sure you keep looking to leaks. If you have a leak try and tighten that connection just a little more, if that doesn't fix the leak relieve the fuel pressure again and take the connection apart and make sure its good and clean then try again.

Go for a quick drive around the block and leave the car running when you get back and look around for any leaks that might have popped up.

Ok now your all done, enjoy your new more durable/better looking/ ready for a billet rails or an intercooler fuel lines!
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