240D - replace rusty fuel lines with hose? - Page 2 - PeachParts Mercedes-Benz Forum

Diesel911 · #16 07-08-2013, 06:35 PM

Quote:

Originally Posted by efm-7

It just seems like one of those "too easy to be good" solutions.

I read a thread on some cummins truck forum that discouraged the idea but nobody gave a real reason as to why not.

The only detraction from Hose is it does not last as long. An optimistic life span would be 10 Years.
The Fuel Tubing lasted 29 years on My Car before it leaked.

Main thing is the Hose is inexpensive if you buy a large roll of it and not labor intensive.

I forgot to mention I think Nylon Tubing can also be used but you would need to contact a Seller or do an internet search for the specifics on that.
There is also that Tygon Tubing that is similar to the Plastic Tubing that is used on the Fuel Injection Pump Fuel. Not sure what the cost would be on that for about 5/16" OD Tubing.

Chad300tdt · #17 07-08-2013, 06:39 PM

I replaced my rotted hard fuel lines in 2007 with diesel rated rubber hoses and they're still holding up fine.

Leaking fuel lines repaired today

Diesel911 · #18 07-08-2013, 06:45 PM

SAE 30R7 is the Regular Fuel Hose is rated for Diesel Fuel
SAE 30R9 DIN 73379-3D Fuel Injection Hose | Goodyear® Engineered Products

vstech · #19 07-08-2013, 10:39 PM

Quote:

Originally Posted by efm-7

Wow, I love this forum. Many replies in such a short period

glad I picked up this "project"

Some areas are obviously worse than others. I figure if I'm going to have the subframe down, might a well do the brake and fuel lines.

The vent line, while a bit rusty, I'm just going to treat.

All the lines above the subframe look like this:
Attachment 113209

I'll be reusing a small portion of the original fuel line within the engine bay so I have something to clamp into.

I think I'll be using rubber or as someone here suggested, nylon.

Interesting your subframe is made of wood...

Simpler=Better · #20 07-09-2013, 09:12 AM

Quote:

Originally Posted by Diesel911

The only detraction from Hose is it does not last as long. An optimistic life span would be 10 Years.
The Fuel Tubing lasted 29 years on My Car before it leaked.

Main thing is the Hose is inexpensive if you buy a large roll of it and not labor intensive.

I forgot to mention I think Nylon Tubing can also be used but you would need to contact a Seller or do an internet search for the specifics on that.
There is also that Tygon Tubing that is similar to the Plastic Tubing that is used on the Fuel Injection Pump Fuel. Not sure what the cost would be on that for about 5/16" OD Tubing.

In small quantities Tygon is around $1/foot form McMaster-Carr. Definitely worth the price under the hood when chasing down air leaks.

funola · #21 07-09-2013, 10:00 AM

The clear Tygon lines (they're polyrurethane btw) will turn brown after a year or so. The clear nylon lines I have are still clear after 5 years, zip tied to the steel lines makes easy install and won't sag like hoses which is much bigger in diameter. I used it to replace Digireditny's rusted fuel line in about 1/2 hour and cured his longtime fuel problems. This stuff is great.

I have about 100 ft of the 5/16 clear nylon left. $1.00 a foot + shippimg.

DrLou · #22 07-10-2013, 11:21 AM

efm-7:

I'd really suggest you completely replace those lines. By way of encouragement: Having just done this job last week, I can tell you it's quite manageable. With suggestions from many guys here - thanks, all! - I replaced both fuel lines, in singles lengths, using 5/16# aluminum line. Sold inexpensively at Aircraft Spruce, and very easy to work with - all bends done by hand. (Like you, I would not have looked forward to bending steel lines in those tight spaces...!)

While you're under there, it might be a good 'maintenance item to pull and clean the tank strainer. After 30 years, mine was badly gunked - pretty common in these cars, I understand. I also replaced the threaded in-tank supply and vent hoses for good measure.

I discovered just how bad all the lines under the car were only after one of my rear brake lines popped! Yes, was lucky I still had front brakes for a while...

Bigger Picture: This has lead to a project to replace all my brake lines, both hard and hoses. (Find yourself a tool - or the skillset - to make the bubble flares, if you're headed down this path!)

charmalu · #23 07-10-2013, 12:29 PM

Check out these guys, they have Brake lines that is a Copper-Nickle Alloy, easy to bend and corrosion proof. haven`t priced it, may be pricy, but hey, nothing is too good for our babies, right?
You can buy the Wife a new Dress next month, ya don`t want he to get mean on ya.

FedHill Brake Line - Where to buy brake line, fuel line, brake line flaring tools, brake line nuts and brake line fittings

I wonder how the aluminum fuel lines will hold up to the salt corrosion.

Charlie

funola · #24 07-10-2013, 01:05 PM

Charlie, Autozone sells cu/ni brake lines in 50' rolls.

I'd not recommend alum fuel lines under the car for possible corrosion, vibration ( thin wall) and lack of toughness issues.

Simpler=Better · #25 07-10-2013, 01:18 PM

Quote:

Originally Posted by funola

Charlie, Autozone sells cu/ni brake lines in 50' rolls.

I'd not recommend alum fuel lines under the car for possible corrosion, vibration ( thin wall) and lack of toughness issues.

I've heard of rotrods running alum lines without problems

efm-7 · #26 07-10-2013, 02:54 PM

I live in a VERY salty, humid area. Rust haven.

I wouldn't feel too comfortable using aluminium line due to galvanic reaction between steel.

This all started because I found rust in my fuel tank... Followed the lines to find that I should replace the fuel lines as well as brake lines.

Funola - how do I attach said nylon line to the fitting on the tank or to the rubber lines in the engine bay?

DrLou · #27 07-10-2013, 04:35 PM

There won't be any galvanic (half-cell) reactions going on in the case of your fuel lines, if installed properly. The rubber grommets - assuming you get them all installed properly, do the job of ensuring this....

There will be no steel-on-aluminum connections. Our Daimler engineers thought about this, too, in the original design; once installed properly, there is no metal-on-metal contact anywhere along the fuel (or brake) lines.

In addition, the same grommets provide protection against any slow abrasion/potential perforation problem. This is the one potential issue which might have concerned me. So: quality of installation the key here.

Finally, I wouldn't have great concerns about corrosion damage. You're correct, though; Aluminum doesn't rust, it corrodes. And this micro-layer of corrosion is tremendously protective against further corrosion. It's precisely this property of Aluminum which makes it the go-to material for outdoor furniture, for example (or for the shades on the lanterns here in town...)

Once that fine layer of white dust (Aluminum Oxide) forms, it's a protective barrier.