I know this may seem like a simple thing, but one of the flare nuts on my brake line is seized, and nothing will shift it. Don't want to ruin the nut, does anybody have any suggestions? Was using the right size flare nut spanner (3/8 inch if that helps), but even that seems to want to burr the nut. Thanks for any help you can provide. Noel
If it is that badly seized I reckon you have some work to do anyway. I would sacrifice the nut and get it out any way you can...vice grips ...anything. New nut, re-flare line and you're good to go. Probably not what you want to hear but that's what I would do. Pete
I think Striper has it, I wouldn't trust the nut again even if you do get it apart, may have been overtightened and pulled some threads.
I've used heat to break badly corroded nuts and bolts before. Not sure if it would be the right thing to do for a brake line though. I'd probably cut the brake line with a hacksaw and use a single-hex socket to get the nut off, then re-flare the brake line if you have enough length left. Good luck.
If a flare nut wrench won't work and you can get a vise grip around it, sacrifice and replace as suggested.
Seen the problem many times as stated above a little heat goes a long way and if all fails cut the line and go the socket route
Let me insert my "Good tools are not cheap, cheap tools are not good" rant here. Line wrenches are one place where it really pays to buy the better stuff like Snap-on, Craftsman, etc. I have ruined some fittings because of cheap line wrenches. The cheap Chinese wrenches are not machined to as close a tolerances as the better stuff and don't grip the fitting as snugly. Thus, more likely to slip and damage the fitting. Also on the cheap stuff, if you pull hard on a tight fitting, you can sometimes see the part that is supposed to grip the fitting flex and bend slightly as you pull on the wrench. Then once it slips and you round off the corners of the fitting, nothing but a good pair of vice grips (insert rant here about the cheap Chinese knock-off vice grips) will get it, and all you can do is replace the fitting and re-flare the line.
Use heat... but do it right. Heat the nut and then let it cool completely. NEVER try to turn one when its hot. When hot, metal expands and will actually become tighter. After cooling it will be smaller than original and will likely have broken the rust bond holding it. JOE
If you really want to do it right... heat or vice grips to get the tubing loose. Then replace the line back to the next connection. If it is as tight as you say then it probably is more than just the nut threads holding it. The tubing nut is most likely frozen to the tubing also which means the tubing is compromised too. We have wrung off a bunch of brake lines when the nut finally broke loose at the threads but the weak tubing underneath stayed frozen and twisted off. I always was actually pleased because we found a dangerously weak line that could have been easily over looked. Of course the customer always said "it wasn't twisted when it came in here" but I knew his car was safer and I was not going to be blamed for a tragic accident. If the next connection is just as difficult then I'd go the whole nine yards (on my personal car). Brake lines don't normally fail when slowing for a stop sign. It's more often in a panic stop when you need to stand on the pedal to avoid the kid on the bicycle. I don't believe in replacing perfectly good parts but risking your life or that of someone else over a 15 dollar repair just doesn't make sense to me. If it's so frozen that a line wrench can't break it loose then I don't spend any more time trying to save a few pennies. Can I get it loose? Probably but it just ain't worth it. JMHO
Thanks for the help guys. You are right, replacing it is the only option. Was just being impatient, wanted to do a quick fix, so I could take it round the block afew times, see what else is wrong. Haven't driven the old girl yet, just picked her up, and keen to get the to-do list started. Just did!!!!
Here's a bit of wisdom that deserves a 2X endor*****t. If you've ever had a brake failure, you'll know why. Thanks, Tommy!
Here is the drill.... If it will not come loose on the first attempt with the proper line wrench STOP ! Grab your GOOD vise grips , not the old worn out or cheap ones.. Lock them down on the nut TIGHT. This slightly distorts the nut. Break it loose, remove the visegrips and go back to your line wrench to finish the job. Then you can take a file to the nut and clean it up.. Most often this method leaves a barley noticable mark on the nut and is completly servicable. Works for me 98 % of the time.. The other 2% is just plain ugly LOL ! Dave
Soak it with Kroil or some kind of rust buster. Heat with a torchlightly and it should come right out Butch with no damage. If rusty replace line, maybe all of them. Butch
Here is a WARNING!!! Brake fluid explodes when heated!!! I rebuild Vintage Mercedes for a living and often have to reuse special brackets etc they use for the rubber hoses. The only way to get these 50-60 year old ******s undone is to heat the brake nut to red heat . This Always causes bubbling and exploding brake hoses so I know what to expect. Cutting parts off is not an option in my case so i use the hot wrench with plenty of caution.
I had a similar situation with my trans cooler lines when I pulled my radiator. I soaked them overnight with PB blaster, then got to work making an appropriate tool to remove them. I used a good flare wrench, then took a 3ft length of thin wall steel tube I had laying around and crushed it down a bit in a vise to make it "square" enough to slide the the wrench into the end with a tight fit. Couple whacks with a rubber mallet and you now have flare breaker bar. You may or may not have the clearance to use that. I had to pull my water pump to get clearance (no prob since it was on the way out anyway...). Worked for me though
Put a small wire wheel in a drill and clean up the fitting, line and area around it so no surface rust is helping to hold things in place. If you can get at it, tap the flats of the fitting with a hammer, better still to hold a dolly, hammer or block of steel- something heavy, against the opposite flat when you tap on it. Soak it a few times with a penetrating oil then make sure the hex is clean and dry before you put a wrench on it. As others have said, use a quality line wrench.
Are you just trying to get it apart or trying to salvage line and cylinder? Well, a look will tell you if the problem is the nut is seized in the cylinder or worse - the tubing is rusted in the nut also. Penetrating oil first. Like Dave Lewis said previously, I always use vice grips and work it back and forth until it comes loose. If it keeps on turning the line with it cut the tubing off and use a six point socket to get the nut off. If the nut is really on there no line wrench in the world will get it off. I have found once you break it loose the tubing wrench will work. Those nuts are too soft and any wrench will round them off even Snap-on. I also have a set of Snap-on weatherhead sockets. They will round the nuts off also.
Oh Ya!!!!!!!!!!! I was working on a van in my garage and I had old carpet laid down on the floor so Im not crawling around on cold cement. Well i heated up a bleeder and the rubber brake hose blew out right at the crimp and caught the rug on fire. Thank God it blew in a way that it didnt get me. Not pretty
Heat fitting red hot,douse with cold water then turn....usually works the first time. If not repeat... Do take warning that heating a fitting too much going into a flex line will cause the line to burst and as stated brake fluid is flammable.Keep a sufficient water supply handy in case of a fire! If I have to replace the line I just cut it off with side cutters close to the fitting then use a good 6 point socket to remove the fitting.
a little trick i learned after you get it off or replace it slide the nut back up the lind then us antiseze between the line and the nut also use it on the threads when you put it back together. i even use it on the bleaders.
What I do for a brake cylinder is remove the cylinder bolts,pull it out a little bit from the backing plate,then hold the flare nut and spin the cylinder.Now a little heat from a propane torch,try to avoid red hot, on the nut,work it back and forth gently until it's free.Brake fluid burns? You bet it does,but it just sorta flares up from the open line and makes more smoke and stink than inferno,safety gl***es and leather work gloves just to be safe.
Vise Grip makes a special pliers for removing flare nuts the #7LW. I always get them loose with this one.
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