Flare Fitting Won't Seal
Thread Starter
Instructor
Joined: Jun 2019
Posts: 232
Likes: 14
Flare Fitting Won't Seal
What is the trick,, the secret, to getting the flare fitting to seal in the calipers. I work it in, then back off, then a little farther in, then back off, etc... until it feels firm and tight. The hose to brake line fitting is the same as the hose to caliper. After hours of back and forth, in and out, watch and check for leaks, there seems to be two that just won't seal. Should I just drive for a week or so and watch the master cylinder and hope that they seal on their own?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Brake lines SHOULD BE double-flare...
P.S. If you are forming stainless steel tubing, you need VERY good forming tools because of SS material hardness. Carefully inspect flare sealing surface and mating part sealing surface for imperfections or debris. If you don't see any problems, put a light wipe of grease on the mating part contact area and assemble it again. This will allow further tightening and possibly better sealing. If that doesn't work, go with the Parker flare gaskets.
P.S. If you are forming stainless steel tubing, you need VERY good forming tools because of SS material hardness. Carefully inspect flare sealing surface and mating part sealing surface for imperfections or debris. If you don't see any problems, put a light wipe of grease on the mating part contact area and assemble it again. This will allow further tightening and possibly better sealing. If that doesn't work, go with the Parker flare gaskets.
Last edited by 7T1vette; Oct 25, 2019 at 05:40 PM.
Safety Car
Joined: May 2004
Posts: 4,364
Likes: 1,588
From: los altos hills california
If you've done all that and it still leaks, and all the other flaring recommendations her, go with the soft washers.
Melting Slicks
Joined: Sep 2010
Posts: 3,310
Likes: 697
As said above if using a SS brake line you need a top of line flare tool. I have the East Wood flare tool that was about $250. I haven't used it on SS but it flares that "new" nic-copp" ? line like butter. Buy the line by the foot at Oreilly's.
Having said that proper line prep is critical before flaring. Cut the line and then deburr the end of the line to create a clean internal surface and outside radius.
Plenty of lube as you make the first flare and second double flare.
I haven't used the washers listed above but they could be life savers.
Having said that proper line prep is critical before flaring. Cut the line and then deburr the end of the line to create a clean internal surface and outside radius.
Plenty of lube as you make the first flare and second double flare.
I haven't used the washers listed above but they could be life savers.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Pro
Joined: Oct 2011
Posts: 743
Likes: 71
From: Jarrettsville Maryland
I've had troublesome flare connections in the past. One thing that sometimes helps is taking some coarse-ish sandpaper to the flare connection and roughing it up a bit. That way, when the flare is tightened, all of the peaks that the sandpaper missed will squish against the other side of the connection and fill up the valleys the sandpaper made.
Racer
Joined: Jan 2011
Posts: 336
Likes: 81
From: Southeastern MASS
Is this a new, reproduction brake line? I've had an issue with lines I bought for my 69 Z/28-had a joint that leaked no matter what I tried. I took it apart and had a look with an eye lupe ((a small, hand-held magnifying tool) and discovered the flare had a scar across the surface-no way that was ever going to seal. Good luck.
Peter
Peter