Date registered: Mar 2010
Vehicle: 1989 560SEC, 1989 560SEL, 1995 E420
Mentioned: 9 Post(s)
Quoted: 580 Post(s)
Replacing 'Permanent' Fuel Lines
I noticed a blister the other day on one of my fuel lines. See pic. After seeing pics on this forum of folks who have lost their beautiful cars to fire, I was VERY motivated to get this fixed.
I was reluctant to modify a design that MB engineers came up but did. I cut off the 'pressed-on' or heat shrunk on or how ever they were installed, hoses, and installed standard fuel line and clamps. It was interesting to discover that I could rotate the factory hose against the metal, but it was not leaking.
Next time I get the car on a rack, I'll investigate just how hard it would be to replace the line with the proper MB part. The factory tubing has a hard plastic liner which has been mentioned here before. I hope you can see it in one of my pics. Replacing this with standard fuel line, even though it has working and burst pressures of 150+psi and 400+psi, respectively, makes me a little nervous. That flimsy and flexible line waving around in the engine bay makes me a little uncomfortable.
If you do this, be super careful not to score the barb as you're cutting off the old line. I started by making a cut along the axis of the hose but quickly realized I could not adequately determine the depth of my cut. So I changed to shaving off layers until I could see the barb start to appear. You don't have to completely expose it before the hose will pull off.
This is not a difficult project and the pics should speak for themselves. I read in another post that the hard lines do not come pre-bent from MB. I don't know if the lines spoken of are the ones I was working on but if they are, this fix may make a little more sense.
Last edited by luckymike; 05-11-2015 at 01:04 PM.