Frozen Brake Line Fitting

Trey

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I've been replacing the old brake hoses on our Cordoba and hit a snag. The fronts went fine but in the back I had some trouble. I was able to break the line loose from the hose but the tubing is seized inside the fitting. I've been soaking it in PB Blaster for the last couple days but still no luck. Of course I don't want to twist the line off so I was wondering if there is another way to break things free. I tried just threading the new hose on to the fitting but it's keyed and naturally the key is about 180* from where it needs to be and I don't want to twist the line that much. I only have a propane torch to heat it but I really don't want to use heat. Is there another magic potion I could use to spray on it to break the rust loose or is heat the only option? Hope you guys in the rust belt would have a good solution since you probably deal with this a lot. Here's a pic of the trouble spot.
DSCN2277.gif
 

volare 77

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you could try to tighten with a tubing wrench and then smack the wrench with a hammer to loosen
 

Camtron

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Transmission fluid and hydraulic fluid are full of detergents that will penetrate and break the rust pretty good. 50/50 mix of acetone and transmission fluid works real good as a penetration spray too. I also would apply the method above of tightening the fitting up with a wrench and then giving it a shock with a hammer to help break things up.
Good luck from, Chicago.
 

Aspen500

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Sometimes heat is the only way to get the tubing nut loose. In a lot of cases, it doesn't take all that much heat either.
 

volare 77

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I agree heat works the best but I hate to suggest it because the fluid is flammable .
 

Aspen500

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You do have to be careful but any fire is always very minor. It is best if the hose is unhooked on one end or the other though. Too much heat and sometimes,,,,,,BANG, the hose blows off the the hose end. Don't ask me how I know this.:eek: It will get you attention!

Off the topic (sorry). A few months ago at work, I was changing lower ball joints on a vehicle and when trying to press one of them out, it wouldn't budge. Had the c-frame screw on the ball joint press with as much force as my impact could put on it. Decided to heat the control arm around the joint to expand the hole and hopefully release the joint. You probably know where I'm going with this. After heating awhile all of a sudden KAPOW, the stud blew out of the joint (along with VERY hot grease), hit the floor and put a chip in the concrete. Son of a........ Sounded like Dirty Harry saving the tax payers some money with his 44 Magnum. Never do that again!:confused:
 
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volare 77

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I had a brake fluid fire one time. I was draining the old fluid in a pan and then I heated some nuts on the axle flange. The rag had some fluid on it and caught fire. I tossed the drain pan out on the grass because it was on fire. The grass caught fire. Luckily the fire extinguisher was close by and I put it out. It could have been bad so that is why I am reluctant to recommend using heat for that reason.
 

Mikes5thAve

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When it comes to the sort of rust we get once it gets bad enough between the line and the fitting it turns into one part and it's done. You either replace the line since the rest of it usually isn't much better or if it's clean somewhere accesible you get some fittings and cut it and flare it and replace just the one chunk.
 

Aspen500

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That's pretty much how it is here also. However, I see frequently where the line is fine yet and the only rust is between the nut and tube, just enough to make it stuck. Normally it wouldn't be a problem but with a 3/16" tube and tube nut, there's no way to hold the tube or keep it from twisting without CAREFULLY applying a little heat.
At work, I've replaced every brake line on as new as a 2010 Silverado (we use Dorman SS prebent line kits from Carquest and have done many, many Silverado's, Sierra's, Yukon, Suburban, etc)) and even one of the master cylinder lines on a 2014 Impala when it rusted through so, I feel your pain Mike!
 

XfbodyX

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How about freeing up the other end of that rubber line or cut it, un clip it and remove it and you will have access to the other side of the fitting to spay a tiny bit in there and hold the hard line and use small flat board or any none metal object, whack the line fitting back and it will break free easier then you think. You might just twist a tiny rag into your brake line and and debris will come out when you pull out the tiny twisted rag.
 

Trey

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Thanks for the suggestions. I'll give them all a try. I was leery about using heat for the reasons stated but I'll try it before I give up completely. Most of the time when this happens I don't worry too much about it since new pre-bent lines can be sourced but that's not the case for the J body cars. I looked and neither Classic Tube or Inline Tube offer the pre-bent lines for the J bodies. If all else fails I'll send them mine with the end twisted off and they can duplicate it so they'll have it in their system for the next J body owner. Thanks again for the help.
 

Duke5A

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Do you have a flaring kit and a tube bender? I'd replace with a new section of line and a brass union if heat doesn't do it.
 

Aspen500

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Speaking of brake hoses (sort of), has anyone ever wondered why the nipple the hose is crimped to isn't barbed or have a bead? It's just a straight tube. I first noticed it when the hose blew off the left front on my car 31 years ago and caused the radiator and fan to try and occupy the same space at the same time when the failed hose caused "an incident" with the back end of a '77 Charger.:( The hoses were only a couple years old, I replaced them when I bought the car in '87. The outer rubber was split and the cords were exposed so they got replaced first thing. Since then I've seen it a few more times at work, usually when the crimp collar rusts away and the car gets towed in with "a soft brake pedal" (or worse yet, DRIVEN in:eek:). It just seems strange to me something that could have 1,000 lbs+ of pressure is made that way. I know the crimp collar is what holds the hose on, not really the pressure on the nipple, but still.............Just and observation.
 

High Speed Pursuit

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I am betting it will only take a Bic Lighter because of the soft metals involved...it will heat up fast....get a helper to hold the flame while to try to loosen it with a cheater bar at the same time, because it will also cool quickly...if u lay the lighter down, pick up the wrenches, get oriented, etc, your heat advantage will be gone. Then go to a little larger flame source if a Bic is not enough, before u take the torches to it.
 

mgbeda

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I second the 50/50 ATF and acetone blend. I used it on my 76 Cadillac a while back and got out every exhaust manifold bolt without breaking any. You have to shake before using as they separate and it eats paint, but otherwise it is magic.
 

Camtron

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Lol I worked with a retired mechanic from the Army for awhile at, O’Hare. He told me about the acetone and transmission fluid mix after watching me throw a can of PB Blaster across our shop. I employ it regularly, never lets me downs.
 

80CordobaLS

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Penetrating fluid, vibration, time and heat is my order of attention with rusty parts.

Apply your favourite penetrating fluid, and tap the joint/connector lightly quite a few times. If that doesn't work, let it sit for a while (hours, day).

If it still doesn't budge, add heat. Get it hot. Put your flared end wrench on it and get it hot too. Try to get it to budge, even the tiniest amount. If it moves at all - even if the tubing is still seized in the nut - hit it with penetrating oil. And move it BACK. Vibrate. Time. Loosen it that tiny amount again, and back, and repeat. Keep at it, with the heat, penetrating oil, and gently moving it back and forth a little bit more at a time. Tap the line gently. Be patient. Eventually you'll get the rust broken free and the fluid will be able to get into the crevices as they get slightly larger.
 

Aspen500

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I've found that the best penetrating oil is Aero-Kroil. Expensive but worth every dollar. Seems to be sold only in a very few places. I've bought it on-line right from Kano Labs and, unlike PB, Kroil smells good!

Today at work when I had to almost heat the center of both rear rotors on a 2014 F-150 cherry red, and then use a really huge BMFH (sledge) and after swinging the sledge until my arms were going to fall off, rattle them with the air hammer, start swinging the sledge again and, they FINALLY came loose from the axle flange. Son of a.........................I don't think even Kroil would have helped on those friggin' things. I mean, the truck was nearly 6 years old, what did I expect?:eek: Thank you Wisconsin DOT and all your road salt. Grrrrrrrrrrrrrrrrrrr.
Moral of the story: At times the only thing you can do with rusted things is heat, heat, heat and apply brute force, beating it into submission, heat even more (hotter this time) and beat the living crap out of it. Unfortunately, sometimes that isn't even enough.
 
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