5. Create some extra slack in the factory line, this way if you screw up the first flare, you have a 2nd or 3rd chance for another flare.
THEN get the new line, bend it to shape and make flare to meet the factory line. This way if you screw up the new line, simply go to the store to buy another line for $5-$6.
You rather have excess line than too short.
Excess line (after everything is done) can be gently turned to create a slight "S" shape to reduce slack to minimize tension.
6. During installation of union: finger-tight and turn a bit, leaving a bit of room for further tightening if there is a leak. I use a bit of anti-seize on the nuts.
After everything is bolted back, I pressurize the line to 10 psi.
- Saw leak at 2 separate places. Tightened the nut a bit more.
---> Then bone-dry.
The sealing effect is accomplished by the bubble flare (hard metal by steel)
against the softer metal in the Union (Zinc or Brass I don't know).
- Whatever you do, do NOT allow the reservoir to run dry.
- Test drive around the neighborhood at low-speed 10-15 mph.
Make sure your Parking Brake works in case!
- Then do a few "panic stops".
- Bring the car home and inspect for any leak.
- Leave the plastic cover off for a few weeks to allow you to
inspect your work.
- I posted on separate thread on how to prevent future corrosion.
Follow that thread here:
https://xoutpost.com/bmw-sav-forums/...ake-lines.html
PS: That is all it is not difficult but tedious. As mentioned, good tool and technique is important. ALWAYS make sure the bolt is in place BEFORE
making the flare or bend.
If I do this again, I'd buy a few extra 4.75-mm adaptors (about $7/each on line) in case the pin breaks. In my case, the pin broke after making about 15 flares (some from practicing and some on car flares).
Interestingly, even after the pin broke off from the 4.75-mm adapter, I could still make good flare, as long as the tool is centered.
Anyway, making flare requires patience, some finesse and patience.
That is all boys and girls, not difficult as long as you are SLOW and METHODICAL.