Hey everyone,

Discovered a small pinhole leak in the fuel line of my 1990 240DL (under the driver's seat - the usual hard, brittle, black hose). I have some "regular" extra fuel hose from another project (SAE30R9 rated for high pressure), and I would like to insert this hose from the leak up to the fitting on the injection rail.

I first thought I could use a regular hose barb coupler - however there was absolutely no way I could get the 1/4" barb into the Volvo hose without kinking it. And obviously heating the hose with a heatgun would be a huge mistake.

However I noticed that a 5/16" compression fitting crimps quite nicely on the hose, and provides a leakproof seal (tested with some scrap Volvo hose and an air compressor to 80PSI). I could even use thread locker to ensure the nut wouldn't vibrate loose while driving. However I'm a little uneasy about this - I've seen too many compression fittings develop leaks on water tubing over the years.

Anyone else out there tried this? Or does anyone have any other techniques for a patch like this? Should I just replace the entire line from the fuel pump?

Any help would be greatly appreciated.