My metal fuel lines from stem to stern are rusted in multiple places. There are almost as many spots of fuel hose patch on the line as there are line. What is the best way to replace these?

I have talked with the dealer and the lines for my 83' 300TD are no longer available. I hesitate to use a set of used lines for fear of the same problem, that is if I could locate partable wagon. Can I use any steel metal tubing? Do auto parts stores cary a standard metal fuel line? I'm running biodiesel so copper is out.

Anyone done this or have a simple elegant cost efective solution?

I believe most speed shops should have 5/16 inch metal fuel line that is close to the 8 mm line on your diesel. Check out Jegs or Summit Racing online they probably have it.

__________________
Bill Reimels
Now down to one:
1972 300SE 3.5 W109 (Euro delivery)

Local generic auto parts store.

Bulk roll of 5/16 steel tube.

My last roll was $11.00 USD for 25 foot roll, you need two.

Be warned:
If you replace fuel lines, you will need to replace the brake line that runs with them, bulk tube and fittings for this are at your local generic auto parts store.

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1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

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I have done this many times. I like to take the old line off if possible without wrecking it. Then I use it as a pattern to bend the new line, taping the 2 together with masking tape as I go along. When the new line is all formed I cut off the tape, cut the line to length and flare the ends. Don't forget to put the new flare nuts on LOL. You can borrow or rent a flaring tool at the auto parts store where you get the steel fuel line.

Your local garage can do this if you are not comfortable with flaring and installing fuel lines.

When you put in the finished line the original clips will probably be rotten. You can buy special cable ties with an eyelet for a screw, screw these to the frame and use them to tie the new line in place.

This is a laborious job but the new line is cheap. I don't mess around anymore, if a brake line or fuel line is rotten I replace the whole thing. Otherwise you will be patching and patching like what happened to your car. Put on a new line and it will be good for 10 or 20 years.

This is exactly the info I needed. After I get to the local parts store, buy my 50' feet, carefully remove the orriginals, shape and tape, trim and flare, i'll get back to this post and fill in any gaps and give an update!

I know that some of my brakets are still good. I had to get a new bolt/fender-washer on one of them already

Good stuff. Here are a few of the fine points.

Don't expect the new line to fit exactly, the old one always gets bent taking it out. You will have to give the new line a bend here or a twist there to get it to fit, this is normal. Try to take the old line off without bending it too much.

When replacing a single line you can strap it to the old lines with cable ties. This looks crude but is perfectly safe. I prefer not to do it this way for aesthetic reasons but sometimes, well....

For the type of line that has a rubber hose pushed over a steel line, you can duplicate the bulge the factory puts at the end using the flaring tool.

Double flares are best for high pressure like brake lines, probably not necessary for fuel lines. Do whatever the factory did.

On long lines in difficult locations sometimes you need to make it in 2 parts,or for brake lines buy 2 ready made lines to get the length you need. In this case you can buy a connector fitting, where a brake line screws into each end.

For low pressure like fuel lines you can get a similar connector called a compression fitting, it clamps onto a plain line, no flare necessary. Don't use a compression fitting on a brake line, I know people get away with it but it's not rated for high pressure.

Hope this helps.

A few more thoughts:

When you go to straighten out the new line set the end on the floor and have someone stand onit while you unroll the line along the floor. This is the easiest and best way to get it straight.

To take off the old line don't try to undo the end nuts. Cut the line with a pair of side cutter pliers next to the fitting and remove the fitting with a socket wrench. This is especially important if you are forced to reuse the fittings.

When you flare the line remember "european" flares are different. You only bulge the metal, skip the last step of upsetting the the metal into the flare.

Get new fittings, if they don't have the correct ones you can reuse the old ones as above although you might have to drill out the piece of tube. If they have european lines but not loose fittings you might buy a short line just for the fittings.

Hope this helps. Let us know how you make out.

The comments on flares and flaring tools apply to brake lines. your fuel lines don't need flares, you just push the rubber hose over the steel line and clamp with a hose clamp.

Your going to have to figure out if it is possible to replace the line without removing the rear suspension. You will have to start the rear section of the tube and bend it to match the old line. Under the car and while you in the process of bending it. I you remove the old line and then bend the whole tube to shape you will not be able to get it in without lowering the rear sub frame.
Look at the setup carefully and have a plan before you yank the old unit out.

Dave

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1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

dmorrison you are correct. On my 300SD they obviously fitted the lines to the body before attaching the subframes. I replaced the lines in 2 sections, splicing them together in the middle. It was a bit tricky getting the old lines out and the new ones in at the ends but quite possible. If you are really in a tight spot you can rerout the line, but be careful it doesn't hit anything and remember the suspension can move around quite a bit, and keep away from the exhaust by at least a couple of inches.

You can also use neoprene tubing in tight spots.

I just finished replacing the fuel lines and brake lines on the 300SD today. If anyone cares they are each 15 feet long.