PeachParts Mercedes-Benz Forum - View Single Post - Help - Expansion Fuel tank/ Can I drive w/o one?

lrg · #2 07-09-2003, 01:51 AM

I'm guessing it's drivable temporarily if the tank is at least 1/2 empty. I'd put the hoses in a plastic bag in case they burp a bit. My wagon's plastic expansion tank cracked too and I found I could use a low wattage soldering iron to fix the crack. You basically weld it by pushing hot plastic over the crack. In areas where the plastic seemed thin I cut scraps from the edges of the tank and melted them on the crack(s). I also broke one of the hose nipples and fixed that the same way except that I added a metal tube on the inside (purchased from a hobby shop) and "welded" the base of the nipple with the soldering iron. To be sure it would last I also built up the base of the nipple with JB Weld (be sure you use some mineral spirits to clean off all the fuel around the base and I roughed it up a bit with sandpaper too just to make sure it would stick). At first I tried not using the metal tube but the nipple cracked again in about 6-8 weeks. For a temp fix you may not need a tube but if you want it to last use the tube liner to strengthen it. I did this repair about two years ago and it is still holding fine.