Brake line replacement question

[Bwana Bob]

My rear brake line is rusted and leaking above the rear axle (stinkin' road salt).

I read the threads, it doesn't look like too bad a job, so I'm going to fix it myself. I understand that the brake line is 3/16 with SAE fittings. My Ex is a 92 with only the rear ABS (RABS), so I only need to replace the line up to the RABS valve, which is located on the frame rail.

Question: I understand that the brake components are Bosch and therefore use metric fittings. Can anyone confirm that the lines are SAE but the RABS valve fittings are metric?

I need to know if I should buy metric and English flare nut wrenches.

Also, any suggestions on what length lines to buy?

Thanks.

Bob

 

[wolfnutts]

yes the valve has a metric 3/8 outside thread an a inside to fit 3/16 line not easy to find some times , you may be able to reuse your old one ?? for the line id get a roll of 10 feet so you use one peice of line . an if you are able drop your gas tank outa the way it makes running the new line so much easier

 

[pugsy]

I had a leak around the axle in the fall. You should only need to replace from the flex line to the backing plates - unless you're leak is on the main line and not the lines that run on the axel. This way you don't need to worry about the gas tank.

It was kind of a pain for me as the rust had rusted the lines into the wheel cylinders....so i ended up cutting the lines and just replacing the cylinders that connect to the backing plate (I actually just redid my whole back brakes while I was in there, HW, shoes and all!). I was able to get lines that were about the right lenght with the flare and fittings already on them. I just used a tube bender to curve the line a bit to make it the right lenght.

You don't really need a flarenut wrench...just use a regular combination wrench (open end). However if the lines are really rusted into the wheel cylinders, just cut the line and use a socket to remove them. Then install with the regular wrench.

 

[Bwana Bob]

Thanks, guys.

The main line is rusted and leaking right where it attaches to a bracket on the frame right at the bump stop. The other side of the bracket has a hose which goes to the splitter on the axle.

I checked on the NAPA site and they have lots of lengths and types of 3/16 line, and some adapters, too.

My next question: Are the flares inverted, double or bubble? Also, I assume that the threads on the fittings are 3/8-24.

Wolfnutts, I didn't understand what you meant by "3/8 metric" at the RABS valve. The metric fittings I saw at NAPA were 10-1, 11-1.5, or 12-1 mm.

Sorry for all the questions, but I want to get the right parts before I start disassembling the old lines and making the truck undriveable.

Thanks again.

Bob

 

[wolfnutts]

sorry if i confused you on that 3/8 .metric i just dont know what m.m. size that would be an 3/8 is what i measured it is a red fitting which is metric , ohh an that 10 feet measure i gave you was for a 2 door if ya have a 4 door maybe ad more its a pretty striaght shot along the frame rail just get your tape out an check better to have 8 inchs to much line then 8'' to short

 

[yellowcat]

I went to replace a simple little brake line once upon a time. I replaced it, jumped into the truck, bam, the next line blew apart. I replace that one, bam next one went. You may need to prepare yourself to replace more than one. I would recommend inspecting them all before beginning.

 

[Anime]

Your best bet with the brake lines is to use the stock fittings if they're in good shape. I've had little luck getting the right fittings for ANY vehicle when buying stock brake line that comes pre-flared with fittings. Sometimes you can get the right thread, but then of course the nut is a different size so you wind up needing two different wrenches for your fittings unless you replace them all.

If you can, get a good length of line, buy a double flaring tool (brake lines are double flared...do NOT settle for a single/inverted flare or make it a double flare by smooshing the bubble flare with the fitting..it will leak...not to mention terribly unsafe), then make your own line by putting the stock fittings on the line, flare the ends, and use a mini-tubing bender to gently make all the bends, and you'll have a nice and tight new line. I'd definitely suggest checking all your lines, especially the entire other side on the rear. Maybe even loosen the fittings to make sure the line isn't rusted to where the fittings are seized to the line and snap it when twisted loose. It's a lot less hassle to replace both lines once you have the system open rather than breaking it open again just to do the other line down the road.

I kind of like using flare nut wrenches on the fittings since they're pretty soft, and sometimes you need the leverage when breakin' em loose on a line you want to keep. The suggestion of cutting the line and using a socket is a good one, though.

 

[Bwana Bob]

All fixed

I took the Ex to an old high school friend who has a bigger garage, a vacuum bleeder, a double flaring tool, and he knows how to use it.

I bought some brake line sections at NAPA, a hand full of nuts and couplings (NAPA BK 6413290 and BK 6413295) and , at his suggestion, a new rear flex hose.

We ended up cutting the line amidships at the frame rail, then running new line back along the frame to the rear bracket. We replaced the old flex hose, which was starting to crack. We also replaced the line from the "T" on the diff to the left wheel.

Though I'm57 and he's 55 we had lots of fun, like two kids in a sandbox, and we got just as dirty!

Thanks to all who contributed advice.

Bob

p.s. The self adjusters are stuck, but that's a project for another day!