fuel lines rusted through on 2001 Mitsubishi Montero Sport

the fuel lines on my mitsu montero sport have rusted through and started to leak, i took it to a shop and they said to replace the entire system at a cost of $1200. mitsubishi sells the whole kit(gas tank, pump, lines etc.) but its just the line that leaks am I missing something.

Wow, many days later to reply, I'm sorry I missed your post. I had the same problem. I solved mine for less than $150. The steel lines you refer to are an integral part of the fuel pump, which is, of course, inside the gas tank, which must be removed from the vehicle to replace it. I tried numerous ways to replace just the steel lines, none of which were trustworthy, as they involve high-pressure fuel. So I went online and found a used pump (make sure it's the assembly, not just the motor, as the "hanger" is what contains the steel lines), paid $75. I was able to salvage the gasket, but they're around $6 new. The plastic high-pressure line which runs from the the fuel tilter back to the steel line was $7 from Mitsubishi. Misc. rubber hoses (I replaced all of them) $8. I had to destroy the short rubber connector between the tank and the fuel filler pipe, and the replacement was about $37 from Mitsubishi.

I cleaned up all the rust on the top of the tank, hit it with a good coating of rust-sealing paint. I used Permatex 3 to ensure a good seal under the fuel pump hanger. I spent a while trying to remember where all the rubber hoses re-connected (pictures are scarce). I re-hung the tank, tested for leaks, no problem! Saved quite a bit over your quote. While surely too late to help you, I hope this helps others.
Thank you for your information... I am about to tackle this project with a unit purchased online for $160 (hanger, pump, sock, etc.)... I am guessing that there are four hose connections... Fill, vent, pump discharge, return... Does that sound right? Thank you...
ArtMcL - It sounds right, but honestly, I did the job so long ago I'd be useless trying to remember which was which. I finally ended up going to a Mitsubishi dealer and asking the man at the parts counter to pull this pictures he had and print them out for me. They required some figuring out, because even though the pages were reproduced from the Montero shop manual, they were poorly drawn. Not impossible to decipher, though, as I managed to get it right on the first try. I wish I could offer you more.
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The fuel lines don't cost much, But the labor is huge and they have to provide some kind of warranty after completion