I made new rear brake lines and since I only have an SAE double flaring tool, I made the bubble flares by only doing the first of the double flaring operation. It seems to seal and not leak but is this going to last? What have you guys done that worked? I don't want to buy a flaring tool I'm only going to use once.
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Advance Auto , NAPA , Auto Zone all carry the Euro metric bubble flare
Fpcopo VS posted:I made new rear brake lines and since I only have an SAE double flaring tool, I made the bubble flares by only doing the first of the double flaring operation. It seems to seal and not leak but is this going to last? What have you guys done that worked? I don't want to buy a flaring tool I'm only going to use once.
What type of nut did you use? The back surface of the flare that the nut sits against is different for the SAE vs ISO flares. Since you're using a mismatched flare to begin with, it's possible you used a mismatched nut as well. A mismatched nut can cause leakage from distorting the flare, poor clamping that could potentially cause things to come loose, or put excessive stress on the line causing it to fail. This is in addition to the fact that a partial double flare doesn't form the same sealing surface angle as an ISO flare which can cause sealing issues in the first place. Can it work? Possibly, but you're better off getting the correct tool or just buying a premade line.
I had to shorten the line, so one end was reflared and I used the metric nut that was on that end. I tried to make the bubble the same size as the other ends factory flare. It doesn't leak now but I just wondered if I may have a problem down the line.
Brakes are something that gets done one way, the right way..... There's no substitute for a safe and 100% functional "Whoa Pedal" IMHO correct what you have, doing so may save your life.
