Fuel line sizes.

[su8pack1]

1969 280SL. What size OD feed and return fuel lines have any of you used? In inch mesurements. I ordered a pair from a vendor, but you have to make all the bends yourself. I did but the return line is steel and very hard to bend even with the correct tools. I ended up kinking the 45° bend that goes over the rear axle. I'm thinking aluminum lines. I ordered a hydraulic hand bubble and flare tool as the hand tool I have is a killer to make the bubble end in a steel line. Any recommendations on size and thoughts on using aluminum lines.  My research comes up with several different sizes. Thanks.

[rwmastel]

https://www.sl113.org/forums/index.php?topic=17479

I hope this helps.

[su8pack1]

Thanks for that link, I missed that one. Any thoughts on aluminum lines? I see they're used on many other cars, as they are just easier to shape.

[TJMart]

Thanks for that link, I missed that one. Any thoughts on aluminum lines? I see they're used on many other cars, as they are just easier to shape.

I installed all new brake lines on my car and used Copper/Nickel lines using the Eastwood Tool to flare the ends mentioned in the above post. I don't see why the copper/nickel lines would not work on fuel lines. They are much easier to bend and flare with the proper tools and will not rust. I was very happy with the results.

[merrill]

hello
about 20 years ago i replaced all the fore to aft lines on my sl.

brake, fuel return, fuel send.

at that time i believe i was able to order all 3 lines from the dealership which arrived in a coil.

first step was to un roll and straighten the lines as best i could.
 I think i taped one end to the garage floor and then carefully un rolled keeping the coil as steady as possible and using a foot to keep the line in place as i un rolled.

i ended up bending the lince by hand,   i would tape one end of the original line to one end of the new line
then, slowly working my way down i would bend by hand (maybe using a tool here and there)  and taping the lines
together about every foot or so. 

once i got to the other end, i would to back to the start and double check.

the most fun was re installing all 3 lines in the car.    new clamps and rubber etc.

hope this helps
j

[su8pack1]

Yes, thanks.

[su8pack1]

Finally got my fuel lines done. After getting the lines bent the new steel line ended up 6" to long so I had to cut that off which then required a new bubble flare for the rubber hose to connect. After going through 2 of the cheaper kits that couldn't flare the steel return line I bought the Mastercool Universal Hydraulic Flaring Tool Set which did the job. Expensive but worked good.

[su8pack1]

Pic

[su8pack1]

Pic

[su8pack1]

pic

[su8pack1]

pic

[rwmastel]

Silly question - why/how do metal fuel lines "go bad"?

[mdsalemi]

Silly question - why/how do metal fuel lines "go bad"?

Steel fuel lines, like any other steel part (particularly anything living in the menacing underside of a car) can rust.

Pure copper (along with other metals) can possibly “work harden” and crack or break when subjected to stresses.

Either situation perhaps rare…but it does happen.

[su8pack1]

After finishing the water pump, and crank shaft seal replacement I had the engine running for a few minutes and noticed a puddle around the back driver side tire. Gas. Both lines had a pin hole in them and were leaking. A couple years ago I replaced all the brake lines and rebuilt all the calipers and 4 new tires and battery. About 12 years ago I replaced the fuel pump, cleaned and sealed the gas tank. 6 years ago I replaced the injectors and had the injector pump rebuilt. I bought the SL back in 1982 and she's a good car, but like any other it takes a lot to maintain it.

[rwmastel]

Ok then.  I guess metal brake and fuel lines are now on my yo do list.

[su8pack1]

Finished. All new fuel hard lines, and rubber lines hooked up. That took some time.

[mdsalemi]

Finished. All new fuel hard lines, and rubber lines hooked up. That took some time.

With nice and proper clamps! 👍👍👍