Rusted brake lines?

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canada karl
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Joined: Tue Jan 06, 2009 3:50 pm

Rusted brake lines?

Post by canada karl » Thu Jun 11, 2020 7:37 am

I'm attempting to replace an old brake line. After 50 some odd years the nut at the caliper rusts to the point where it's welded in place. Because of this I might have to replace most of the brake lines with new at some point but i was hoping to just do the one rear line from the rear junction to a rear caliper for now. Pretty sure this cant be done because it's the same issue at every connection?
I've soaked the connection overnight with PB Blaster,gave it a rap to set up a vibration so the penatrant would soak in,tried to work the nut back and forth with a 'claw foot wrench" but no luck. I'm ready to try heat with a propane torch??? If the line breaks at the caliper then the real fun begins.
I'm thinking I might just have to bite the bullet and and disconnect the main line at the pressure regulator or master cylinder( this area is out of the weather and the lines there don't look as rusty) and replace everything from there back. Anyone been there done that? :idea:
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

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Re: Rusted brake lines?

Post by keehn » Thu Jun 11, 2020 7:59 am


I would heat up the fitting, but expect to replace the brake fluid afterwards. Heat solves most all rust problems. Trick is to heat it to cherry red and let it cool. Then it should be an easier removal.


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