Dave:

It's unusual for the fuel injector lines to leak, esp. (as you point out) they have a special type of fitted surface that is self-sealing and does not require sealing washers. Since the problem first happened when the temp. was low it sounds like they need to be loosened and re-torqued to the correct torque since cold weather causes metal to shrink a bit more than when it is hotter. Unless some ham-fisted jerk over torqued them and damaged the contact surfaces - if this happened (as shown by deformed contact surfaces, ridges in the metal, perhaps even cracks) then the damaged ones will probably need to be replaced (a local junk yard may have them, or M-B & lots of $).

Do you have the special wrench made by Hazet that fits the injector line nut? This tool is a must have to properly loosen/tighten these nuts (its like a flare-nut wrench for brake lines, hydraulic lines, etc. only made to work for this application). I do not believe Fast Lane has tools, but try them first. If Fast Lane can't help then Performance Products sells this tool for $43.50, part no. 58-014.

The nuts are torqued to 18 ft. lbs. or 25 Nm.

If you still have problems the Diesel Forum members have a wealth of knowledge and someone may have experienced this same/similar problem.

Good Luck!
Tom

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1977 300D: 300,000+ miles

American Honda: Factory Trained Technician & Honor Grad.
Formerly:
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