E34 fuel line replacement help

[Spaceturtle917]

I just got back from my excellent indie mechanic. We got the car on the lift to inspect the exhaust. Exhaust is the least of my concerns right now because I was just made aware that one of my fuel lines is leaking onto my exhaust. I want to replace all of the lines, or at least the major or troubled ones. I don't know where to start with this. I've done brake lines before and I'd assume it would be similar. The starter question is do I use factor lines from the dealers as I believe they're pre-bent, or do I buy and bend copper lines myself. This seems like a simple job but I don't know anything about fuel systems. The only thing I've done is replaced the fuel filter.

I would assume I would just have to buy part 1 and 2
https://www.realoem.com/bmw/enUS/sho...diagId=16_0134

BTW the car is a 6/1990 535i manual.

[ross1]

Two options; Pre-bent factory lines that will (here's the caveat)once you remove the rear sub-frame, fit perfectly. Or, bend your own from either steel line or the copper/nickel which is WAAY easier to form and flare.
Me? I'd be ordering a spool of copper nickel line.

[south42]

Depending on how bad I have in the past cut the line where it is leaking and but rubber hose over it. If really badly rusted I replaced with copper line.

Andy

[Spaceturtle917]

What about using rubber lines? I've heard that they're just fine now a day.

[moroza]

Rubber won't be as durable in the long run, and to maintain fuel pressure you want as little flex in the system as possible.

I have replaced brake lines without dropping the subframe, and bet that with careful slight bending, the fuel lines can be maneuvered around the subframe as well.

FYI, I was told by my parts vendor that BMW brake and fuel line did not come pre-bent.

[m735is]

The last time I replaced fuel lines in my 95 525i, I bought pre bent from the dealer. They were surprisingly not that much ( a few years ago). I did not drop the subframe completely, I did remove the brace that attaches under the subframe bushing to floor and snaked the lines up through there. There was just enough room to get them in. I left most of the rusty lines in place because the screws for the line holders were not coming out.

[GregT53]

FYI, I was told by my parts vendor that BMW brake and fuel line did not come pre-bent.

Last time I bought OE brake line it was not pre-bent. I suspect the same is true for fuel line. Putting in rubber line where it was not originally is not a good idea.

[Spaceturtle917]

m735is says it was. I bought brake line from the dealer and can confirm they are not bent. Anyways I'll be doing sub frame bushing replacements soon. I assume that will help with getting the fuel line in.

[m735is]

I just checked my repair notes. I bought the lines from eBMWparts online- OEM lines and they were pre bent. This was on 3/1/2013, so things may have changed. I have purchased fuel lines for my e23 at the dealer, but that was even earlier and they were pre bent.

Doing the sub frame bushings at the same time will definitely help.


The first picture was how mine was shipped (and received from the dealer)-
https://www.ecstuning.com/b-genuine-...d/16121179604/

[jehu]

oy.. I just bought a 540 which was in some stage of having this done. I saw the coiled copper tubing in the back seat and said to myself I'd prefer the OE pre-bent lines but had no idea the SUB-FRAME NEEDS TO COME OUT???? Gonna have the car towed to a shop of a forum member possibly tomorrow to get it back together.. car has sat for about five years .. what might be the condition of the fuel in the tank if it hasn't been drained?

Two options; Pre-bent factory lines that will (here's the caveat)once you remove the rear sub-frame, fit perfectly. Or, bend your own from either steel line or the copper/nickel which is WAAY easier to form and flare.
Me? I'd be ordering a spool of copper nickel line.

[Spaceturtle917]

lmao you win some you lose some i guess.