Joglusker

Hey guys, I recently purchased my first FC (1988 GTU) and I’m loving it so far... while she sits in a driveway because I have no brake pressure So despite being, well, very new but welcome to working on cars, I pinpointed the leak to the end of the long brake hard line that runs from the hood to the rear brakes. Of course, 30 years of rust and salt pretty clearly destroyed it so I read up on how to make a new brake line. However, I just can’t seem to get the actual brake fittings off! I accidentally sheared the rear fitting, front is fine. But after a generous amount of liquid wrench and vice grips, I’m pretty much at a loss here. I heard some people use a propane torch or something along those lines to heat the fitting up and then remove it. But before I resort to buying a torch I’ll likely never use again, does anyone know of an easier way to get these fittings off? Maybe just rust remover, hitting it with a hammer? Just trying to see if there’s anything I’m missing here. Help a guy out please!

rxtasy3

iTrader: (2)

wd-40 is what i use but i've heard pb blaster works good but can't say for sure as i've never used it. but yeah, heat is the last resort.

WondrousBread

I redid mine, they had ~380 000 km so they were stuck on there pretty tight.

First you'll need a line wrench (sometimes called a flare wrench). It's like a normal 6 sided closed end wrench, but it has a notch to slip over the brake line. If you don't use one, you risk damaging the fitting. Vice grips also have the same risk. Get a 10mm line wrench and it makes things way easier.

If that wrench doesn't work (it usually does the trick), you'll probably need the torch. Since you've sheared the fitting, it's unlikely that a line wrench will help, but it's worth a shot.

With the torch you have two options. First, you can heat it as hot as you can get it (safely, and stop if it starts to glow) and then hit it with PB Blaster which will cause rapid cooling and hopefully seep in. This sometimes works. The other effective method is to heat it as before, then point a can of compressed air (the stuff that cleans keyboards) at the fitting and the rapid cooling of the decompressing gas could break the fitting loose. I've done this effectively before, but be careful, since I don't really know what is in the can.

Last last resort is to simply remove the other fittings at the rear tee, gently with the line wrench so you don't damage them. Then order a replacement tee (I got a generic double-flare one on Amazon) and install that with your new line, leaving the old one connected to the old tee.

Be careful. The front to back line is available from Mazda (though I think its the RHD line) if you need it, but the rears aren't. Since you've already researched how to do it, I'll assume you can make replacement lines. But better not to damage them in the first place if the ones you have are alright.

Joglusker

Ok I like what I’m seeing here. I just bought a propane torch. I’ll go grab some fuel and that JB blaster later. I’ll give it a shot hopefully later today. Thanks for the advice guys.

WondrousBread

No problem at all. This goes without saying, but be careful with the torch. That area isn't terribly far from the fuel tank and lines, and I think they share a hold-down bracket not far from it. Keep an extinguisher or a hose nearby, and ensure you only put the heat where you want it. Keep the flame on the torch at the minimum you need to reach the fitting. That area on the interior is on the back of the driver's side storage bin, which can be removed with a few trims screws if necessary so you don't make it too toasty.

Good luck

Joglusker

Yup I’ve got a bit of experience with torches already and the fuel cell/bracket is definitely good to know about. Here goes!

edit: also will have a fire extinguisher on me

Joglusker

After a good 15 mins of trying to reach and heat the fittings, I did manage to get them both off with the help of the propane torch. For anyone interested in doing this themselves, I had to used MAP (yellow benzomatic) propane fuel which gets noticeably hotter, and heat the fitting until the brake line was turning cherry red (very, very hot). It's not too difficult, but if the fitting is stripped like mine, get a really tight grip with the vice grips and pull immediately after heating. It took me about three tries to get, but definitely did the trick. I did use some more liquid wrench on it, but I imagine most of it boiled off anyways so not sure if it helped. Anyways thanks again for all the help.