Returd

I'm redoing brake and fuel lines on my 92 SC400. The rest of the car is pretty clean but the lines, not so much. I suspect this is a common but hidden problem. The steel lines are plastic coated except the section running from the driver side catalytic back to about the fuel filter. There are 3 plastic covers that are intended to shield the lines. The line sections under the covers aren't coated and the covers tend to trap crud and aid in rusting the uncoated lines. At the rear of the car above the rear suspension there are small uncoated sections as well that are rust prone.

I decided to replace the 2 brake lines and 3 fuel lines front to back.

I removed the exhaust right up to and including the driver side cat.

I dropped the rear suspension.

This may be more involved than most folks want to do but I'll document things as I go along. I imagine I'll make a few mistakes and will return edit posts where possible to save others from making the same mistakes.


Edit at job completion.

The Copper/Nickel lines are easy to work with, especially if you have to twist the line to correctly "clock" a bend. The line does not hold roundness well when using standard tube cutters. I gave myself some extra length at the ends of the lines intending to trim back when the lines were hung. This made things difficult when it came to getting a flare nut on later. If doing it again I'd flare at the beginning, and also use a dremel for cuts at the flare locations.

Returd

this post will show my "as found" lines.

Returd

More of the as found photos

Returd

I got started today beginning with draining the gas tank. I tried to undo the tank side of the fuel filter and it wouldn't budge so i cut the line. I had a 10 gallon gas can and he flow was slow so i went to make lunch. bad idea, overflowed so i had to ventilate the garage...

the first line am replacing is the driver side brake line. The fuel line needed to be disconnected as the brake line is interwoven.

I made a plug for the line I'll be disconnecting by cutting a fitting off of my parts car and bending it over. This will reduce the amount of fluid lost as well as hopefully keep the drips from stripping paint off of the cross member (brake fluid strips paint).

the second photo is the removed line.

third/fourth photo is a part and a full coil of copper/nickel tube and my tube straightener.

the next photo is various tube benders and cutters etc. The copper nickel can be hand bent but I prefer cleaner bends using my benders.

the net photo shows the cut fuel line. I'm holding the wood up behind the cut so you can see the cut in front of it.

I chose to reuse the fitting at the cat as it has a long shoulder on it. I have stainless fittings in the bag which I would have preferred to use.

The final photo is the bent line beside the old line. I chose to omit the connector that couples the short section from the flex line to the long piece. I figured with the rear end out I could eliminate 2 potential leak sites. I used stainless steel, rubber lined tube brackets.

I have not installed yet as I want to wire wheel and totally clean up the underside before continuing.

Blkexcoupe

iTrader: (8)

Nice writeup, It's cool to see the detailed pictures. With all that rust, I'm guessing you're from Ontario, Canada and not Ontario, California

Duck05

Very admirable undertaking and will surely benefit the members for years to come..... Jealous of course of your skills and commitment for this project.

Question, though: Did you tackle this to resolve either brake or fuel flow issues or just because of a concern of down the road issues (not that a 25 year old car with the rust you discovered isn't enough)? I have a '92 as well but it has been in "sunny California" so not as much rust build up.....

In any case, keep going and the club will appreciate this thread......

Returd

Yep, Ontario Canada. I did use a heavy duty stripper to get every bit of coating off of the lines. My original plan was to coat the lines with POR15. Prior to stripping they weren't that ugly, but it only takes one thin spot.

Blkexcoupe

iTrader: (8)

Yeah, rust is kind of a scary thing. I've only had to deal with fixing a rust spot once in all my years of working on cars. I used to have a dodge ram van for my family's business, and the paint on the roof flaked off in this indentation where water would build up. This particular van sat for most of the year, and when I finally stripped the paint and rust down to apply POR-15 I punctured a hole into the roof.

I noticed some rust where your subframe bolts on. Are you planning on stripping that down and applying POR-15 or some other type of undercoating?

Returd

I didn't have any leaks but inspected and didn't like what I found. I'll suggest even warm climate cars can have this problem. The heavy plastic line coating isn't present for the length of the runs under the plastic shields. Leaves or other debris will likely build up under the covers, act like a sponge and cause lines to rust.

I'm a do it right the first time guy. If I had waited for failure I would have had this nagging me every time I went for a drive. I bought this car for long distance comfortable trips and failing somewhere miles from home isn't fun.

I'd suggest other SC owners pull the covers and have a look.

Returd

I've already wire wheeled the rust areas and will be doing 2 coats of POR15, POR15 topcoat and then 2 coats of Rustolium brush on rust proofing.

I typically fix things so I don't ever have to return to that problem, which is why I'm running stainless lines. I'm also using anti seize on every threaded fastener/connection I touch.

I also found a Supra torsen LSD that I'll install while I have the rear end out. Other than the LSD and LS400 brakes the car will remain stock. Oh I also added an aftermarket Kenwood stereo/nav system, rewired and replaced speakers/sub, but that's it for mods......

Returd

I'm posting this so others will know where to inspect for rust. nothing was serious, just surface rust. I used various wire wheels and included a shot of one of the strands in my knee. I used a face shield but got harpooned many times elsewhere. I just finished cleaning with POR heavy duty degreaser. Following that is metal prep and the 2 coats of POR15 as recomended. I've gotten in the habit of first coat grey, second coat black. I do this to ensure I get the second coat everywhere, easier to see thin spots with 2 colours.

dadswrld

This is beautiful work! Thanks for your insight and share. I've subscribed.

Returd

A few photos of minor surface rust clean up. I'm a big fan of POR15. What you're seeing is a white topcoat over the POR. I followed degreasing, metal prep procedure then applied grey POR. I then put on a second coat of black while the grey layer was tacky. I then applied white topcoat to tacky black layer. I will be covering the bulk of the "whited" areas with Rustolem brush on undercoating. this will be bulletproof and color matched to the factory undercoating.

If you folks want more of my POR process documented chime in and I'll do a separate thread.

Returd

Spent a little time with the lines today.

the copper/nickel lines are super easy to bend and will be easy to adjust once I put all the brackets back in.

I'm using a copper anti seize on the flare nuts, Loctite 37229.

I'm just about to start the fuel lines and thought I'd mention the two fuel line brackets I'm pointing to in the photos. It appears the lines popped out of the brackets some time ago and have been rattling freely, wearing down the brackets. This means the lines are moving when driving, and could wear a hole in the tube eventually. I suggest you folks check these on your cars. I think a zip tie around the lines and brackets will solve this issue.

I measured the line length before bending today. I cut a rough length of 190 inches. I started my bends in the middle of the line at the fuel filter location, as it made bending easier. While bending the line is a pretty long rod that has to move around when making the bends, the middle was slightly easier starting point. When all done I had roughly 12 inches of waste .

I am also going to be forced to use steel flare nuts for the fuel filter and fuel rail hose connections since I've been unable to find any stainless versions.

I'm going to leave the pressure line until last in case I manage to find some in the mean time. In case someone has better search skill than me here's what I'm looking for: Stainless Steel flare nut for 45 degree double flare, tube size 8mm, nut thread 14mm x 1.5 the thread pitch.

LeX2K

If you haven't already make a new thread, using POR-15 and rust repair in general is a valuable topic.