Yes im pretty sure they are compression fittings though i guess i cant know for sure until i disassemble them. Thats not only bad practice its just not safe.
C2 Corvette Restoration The Ultimate Brake Guide
Are compression fittings safe for brake lines. Not safe but legal. It is acceptable to use compression fittings in a vehicle that is not meant for public transportation such as an off road vehicle used for play or a farm vehicle or work truck that is not used on public roadways. Some people argue that they are safe for use since they have already tried and tested them. If you are repairing the brake lines in a vehicle that is not a passenger car used for everyday road travel and transportation compression fittings are an acceptable brake line repair. Compression fittings are equally admissible to use on brake line repairs when the repair is a temporary one. The vehicle code only cares that the brakes work.
Single flare plumbing unions are a big no as well. Compression fittings arent designed for high brake line pressure and can leak during heavy braking. Hardware store or parts store brass compression fittings are not the same deal. Again it is only acceptable to use compression fittings in a car that is not used for public transportation. The vehicle code does not care about what fittings are connected with. Compression fittings will fail in brake hoses.
In addition compression fittings are known to leak when used on brake lines causing a loss in brake fluid and ultimately failure of the braking system. Many states have banned the use of this repair on passenger vehicles too. There have been a lot of controversies regarding the use of compression fittings for brake lines. This is based off of the fact that i know the mechinic doesnt have a double flaring tool and when they made up a short peice of brake line for me they did use a compression fitting that matches exactly what i saw used on my. Industrial compression fittings such as swagelok or parker hannifin are good to several thousand pounds and are completely safe for use in brake systems but that doesnt mean your state inspector will know the difference. You cannot under any circumstances use compression fittings to repair the lines on a public transportation vehicle.
What you cant do is use compression fittings or single flare plumbing unions to make a brake line splice. Experts claim there are certain dangers in using these fittings.
Gallery of Are Compression Fittings Safe For Brake Lines
