Replacing Entire Fuel Hardlines

I have a 1993 Dodge Stealth ES (non turbo, non AWD). Owned since new. In the mid 2000’s developed a fuel leak and at that time there was not much information on the cars. Came to realize it was coming from the pipe coming out of the sending unit which had corroded through. Spent the next number of weeks/months trying to get the sending unit out with no luck as the nuts had corroded/seized. Then life happened and the car has sat in a garage for the last 15 years. Now looking at getting back to it. Came across a number of videos on the car including this forum and YouTube channel. Thank you very much, it’s awesome. Because the car has sat, there is A TON of work that needs to be done to it so I figured I would start back where I left off. I know I need a new sending unit and given the appearance of the tank I’m probably going to need a new one of those as well, especially since I can’t get the sending unit out. The fuel lines under the car appear rusted as well, so my question is what is the size of the hard fuel line and return line that runs under the car from the sending unit to the filter. I read some other posts regarding it but I’m still not sure of the size. Also since I am replacing the lines is there a better/easier way to do it with a more universal size/type of line or setup. Sorry for the length of the post, but I thought the background was important.

Hi and welcome, I think not so far back, someone asked the same question. I believe the diameter of the brass looking pipe is 8mm.

I think that was for the metal pipe coming directly out of the sending unit. I’m looking for the hardline that runs under the length of the car (from the flexible pipe connected to the sending unit to the fuel filter in the engine bay). Unless they are the same size.

Welcome to the forum.
The high pressure line is 8mm and the return is 6mm.
They are made from steel and then lacquered for protection.
The yellow look is where the lacquer has tarnished.
The best way to replace the lines at a good price is to buy the straight steel line and a tube bender. Both these items are cheap.
Remove the old lines without bending them. Lay the new line next to the old one. Use your pipe bender to copy the original bend pattern.
Fit new ends as required and clear coat the finished product.
You should be able to get a near perfect reproduction with a little time and care.


That’s awesome, thanks Joe. It’s great to find a forum like this. I was actually looking at copper nickel lines instead of steel because they apparently can be bent by hand and are corrosion resistant. Just not sure if they are available in the 8mm and 6mm sizes. I’m sure it won’t be easy getting the old lines out, but I’ll do what you suggest to get the best fit.

Actually is that outside diameter or inside diameter. The closest I can find here in the copper nickel is 5/16” and 1/4” sizes.

Those are outside diameter.
You will not find the steel lines in autozone.
You will find it at hydraulic and pneumatic supplies.
Copper lines are for DIY bodge jobs on junk cars. The steel lines have lasted 30 years but I have replaced copper ones after 3 years.
You will also need to check on the safety aspects given that your gas has ethanol content. I believe that ethanol reacts with copper. There is also a risk of the copper cracking near to the rubber hose because of flexing.
It will take 10-15 minutes to remove the old hose. 30 minutes to make a new one from steel and 15-20 to refit. Doing the job properly will maintain the value of your car, give satisfaction and piece of mind for another 30 years.


I’m talking about the copper nickel (cupro-nickel or nicopp) stuff. Says it’s 90% copper and 10% nickel and is used for fuel and brake lines. Doesn’t corrode and easy to bend. You’re saying to stay away from it.

It is only my personal choice and experience. I am sure that many others will use it quite happily. I just like to keep the cars as they should be. I think that it may be wear and corrosion from grit and winter salt that has caused them to fail in key areas just as with steel ones but the steel is stronger so lasts longer. I will see if I can find some pictures.

As Joe says this is an argument as old as time :joy: copper nickel aka kunifer is ‘more resistant’ to the elements eg roads that are salted etc. than steel however it is softer than steel so there is a strength compromise. I have used kunifer to make brake pipes and it works very well - but is not Mitsubishi original. Kunifer is mainly used on Volvo cars as I think they were the first to use it for brakes. Your other option for fuel lines is a braided stainless steel hose - again this is not original but can be easier to fit as you don’t need to shape it.

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Great information, thanks. I’m going to crawl up under the car this weekend to see just how bad the corrosion is, but from what I can see now it will probably not be good. Even so, I’m sure the gas sitting in the lines and tank for the last 15 or so years is a problem in itself.

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Hello JSP!

I don’t post here often, but this one caught my eye.
I had issues with the connection (not at the hat, but below, where the rubber line met the hardline.
I could NOT, for the life of me BREAK that connection.

I caved and bought this:

Well CRAP, as soon as I wanted to link you to a replacement AN setup from 3sx, their site is down.

Anyway, I bought their kit, which replaced everything from the bottom of the fuel filter and the connection at the hat, and while the AN line was a bit long, it worked perfectly and saved me a ton of work and time…

Sorry if I’m late to the conversation…


Hi Bob
Thanks for posting.

I’ll look for it on their website. Thanks for the info because it looks like I will need to replace the lines. Also have to figure out what to do with the pipe from the sending unit as that was the initial leak where it rusted through.

Site is back up…

Here is the kit I purchased and installed.
Worked like a charm…


That’s very interesting and it’s compatible with all fuel types. Could save a ton of work. I’ll be under the hood next to see what the shape of the fuel filter line is. Thanks for the info.

I’m not sure I understand your last statement.
The way this kit works is, you take one of the supplied fittings and attach it directly to the small curved line coming off the filter (where the end of the hardline coming from the back ends now).
Next you attach the other supplied fitting directly to the fuel hat fitting (where the old rubber section would have attached).
Then its just the simple task of attaching the long AN line to both fittings and then hiding the line under the old plastic “tray” where the stock hard line used to be hidden.
A half dozen or so black zip ties to keep the tray piece up and a couple to secure the extra length of AN line (I tucked that up over the rear axle), and WALLA!

Even at age 59 it wasn’t much of a challenge.

And then you get to do this:

Bob. :slight_smile:

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Most of the lines on my car seem to be rusted out. I believe there is that little “C” shaped line with the fitting that runs off the bottom of the filter that this attaches to. If that’s right, I just want to make sure it’s not rusted out too.

Roger. Copy :+1: