Stripped brake line, need advice
Thread Starter
Burning Brakes
Joined: Jan 2010
Posts: 884
Likes: 84
From: New Boston, NH
Stripped brake line, need advice
Hi all,
I am having a problem that just has me stuck. I am replacing my brake booster and master cylinder, along with the 2 lines from the MC to the distribution block on the frame rail. I removed one line, the forward most one with the larger nut, but the second one is just stuck. To make matters worse, I can see that someone must have attempted this before because the nut head is completely rounded. Perfect circle. I can get a pair of small vice grips on it, but, alas, it just won't budge. I have been soaking it with wd 40 for a few days but it doesn't seem to be making a difference. So, any advice on what to try next? I thought of heat, but just wasn't sure with brake fluid and all, how that would react. Anyway, any help would be greatly appreciated.
Thanks,
Bryan
I am having a problem that just has me stuck. I am replacing my brake booster and master cylinder, along with the 2 lines from the MC to the distribution block on the frame rail. I removed one line, the forward most one with the larger nut, but the second one is just stuck. To make matters worse, I can see that someone must have attempted this before because the nut head is completely rounded. Perfect circle. I can get a pair of small vice grips on it, but, alas, it just won't budge. I have been soaking it with wd 40 for a few days but it doesn't seem to be making a difference. So, any advice on what to try next? I thought of heat, but just wasn't sure with brake fluid and all, how that would react. Anyway, any help would be greatly appreciated.
Thanks,
Bryan
Race Director
Joined: Apr 2011
Posts: 11,183
Likes: 3,335
From: North of Toronto - Ontario
I'm thinking the threads in the block might be toast as well as the line so don't be too surprised if you need to remove it in the long run.
Adding too much heat will probably end up screwing the fluid and contaminating the system, dot3 is only good for a couple-three hundred degrees so even a propane torch is sketchy
If it's a steel nut on the line, cut the line off near the fitting and try getting a 6-point (imperial or metric) socket on, I doubt an easy-out style socket would work.
Or, a 4 or 6 inch vise-grip locking wrench (not pliers, the ones with the really funny looking jaws that are designed to lock onto 3 sides of a nut) and file some flats if you need to so it won't slip
Get the largest adjustable wrench you have and put it on the block itself and go at it., pull the vise-grips against the adjustable wrench so you're not stressing anything else or twisting the other lines
just an idea, barbaric but sometimes brute force and ignorance works
M
Adding too much heat will probably end up screwing the fluid and contaminating the system, dot3 is only good for a couple-three hundred degrees so even a propane torch is sketchy
If it's a steel nut on the line, cut the line off near the fitting and try getting a 6-point (imperial or metric) socket on, I doubt an easy-out style socket would work.
Or, a 4 or 6 inch vise-grip locking wrench (not pliers, the ones with the really funny looking jaws that are designed to lock onto 3 sides of a nut) and file some flats if you need to so it won't slip
Get the largest adjustable wrench you have and put it on the block itself and go at it., pull the vise-grips against the adjustable wrench so you're not stressing anything else or twisting the other lines
just an idea, barbaric but sometimes brute force and ignorance works
M
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
With an already rounded-off flare nut, you don't have many options. I would just go to a tougher Vise-Grip and give it a good 'shot' to break it loose. That almost always works; but it can frequently damage the mating part and/or the brake line in the process.
In the future, you need to buy a good brand of six-point crowfoot flare wrench tool (which connects with a 3/8" square drive ratchet/extension). That is the only type tool that has a very GOOD chance of breaking the fluid line nuts loose without causing any damage. They are sturdy enough that the better brands of tools do not "open up" under loading. Snap-On brand is what I use.
In the future, you need to buy a good brand of six-point crowfoot flare wrench tool (which connects with a 3/8" square drive ratchet/extension). That is the only type tool that has a very GOOD chance of breaking the fluid line nuts loose without causing any damage. They are sturdy enough that the better brands of tools do not "open up" under loading. Snap-On brand is what I use.
Last edited by 7T1vette; Apr 6, 2018 at 12:42 AM.
Pro
Joined: Jan 2003
Posts: 706
Likes: 47
From: Denver Colorado
You may get some additional penetration of the WD-40 by tapping (alright hitting) a punch against the stuck nut once you get it solidly held in that crescent wrench. Also, a real penetrating oil like PB Blaster may help loosen it up.
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Thread Starter
Burning Brakes
Joined: Jan 2010
Posts: 884
Likes: 84
From: New Boston, NH
I'm thinking the threads in the block might be toast as well as the line so don't be too surprised if you need to remove it in the long run.
Adding too much heat will probably end up screwing the fluid and contaminating the system, dot3 is only good for a couple-three hundred degrees so even a propane torch is sketchy
If it's a steel nut on the line, cut the line off near the fitting and try getting a 6-point (imperial or metric) socket on, I doubt an easy-out style socket would work.
Or, a 4 or 6 inch vise-grip locking wrench (not pliers, the ones with the really funny looking jaws that are designed to lock onto 3 sides of a nut) and file some flats if you need to so it won't slip
Get the largest adjustable wrench you have and put it on the block itself and go at it., pull the vise-grips against the adjustable wrench so you're not stressing anything else or twisting the other lines
just an idea, barbaric but sometimes brute force and ignorance works
M
Adding too much heat will probably end up screwing the fluid and contaminating the system, dot3 is only good for a couple-three hundred degrees so even a propane torch is sketchy
If it's a steel nut on the line, cut the line off near the fitting and try getting a 6-point (imperial or metric) socket on, I doubt an easy-out style socket would work.
Or, a 4 or 6 inch vise-grip locking wrench (not pliers, the ones with the really funny looking jaws that are designed to lock onto 3 sides of a nut) and file some flats if you need to so it won't slip
Get the largest adjustable wrench you have and put it on the block itself and go at it., pull the vise-grips against the adjustable wrench so you're not stressing anything else or twisting the other lines
just an idea, barbaric but sometimes brute force and ignorance works
M
I misspoke before, the line is stuck in the Proportioning valve, not the distribution block. Don't know if that makes any difference in terms of what needs to be done. There's just not enough space to get a larger set of vice grips on the nut so I'm thinking I just need to take the PV out and work it from there. I will give it one last go with some PB blaster though. Thanks
Race Director
Joined: Jul 2004
Posts: 12,708
Likes: 329
From: Scottsdale Arizona
I misspoke before, the line is stuck in the Proportioning valve, not the distribution block. Don't know if that makes any difference in terms of what needs to be done. There's just not enough space to get a larger set of vice grips on the nut so I'm thinking I just need to take the PV out and work it from there. I will give it one last go with some PB blaster though. Thanks
Race Director
Joined: Jul 2004
Posts: 12,708
Likes: 329
From: Scottsdale Arizona
Another thought. I don’t have my car nearby to check, but I remember getting better access by removing the front wheel and going at it from the wheel well. Might help a little.
Last edited by CA-Legal-Vette; Apr 6, 2018 at 10:27 AM.
Thread Starter
Burning Brakes
Joined: Jan 2010
Posts: 884
Likes: 84
From: New Boston, NH
Melting Slicks
Joined: Mar 2007
Posts: 2,520
Likes: 11
From: Hinckley OH
These have worked for me on rounded off nuts and bolts. You can cut the line off then use one of these on the fitting. You will want to replace that line since the fitting is aready rounded. http://www.sears.com/craftsman-10-pc...FUu_swodtOsFDA
Thread Starter
Burning Brakes
Joined: Jan 2010
Posts: 884
Likes: 84
From: New Boston, NH
Just wanted to thank everyone for their input and to update the thread. Two days of PB Blaster and the nut broke free. The darn thing was seized on the line as much if not more than the threads were seized in the Proportioning valve. Anyway, the line is off now and progress can resume. Thanks again for the help and advice.
Bryan
Bryan
Thread Starter
Burning Brakes
Joined: Jan 2010
Posts: 884
Likes: 84
From: New Boston, NH
Small pair of vise grips, tightened down as much as humanly possible, and as much torque as I could muster while leaned over the fender. Basically, PB Blaster and brute force.