Volvo Maintenance Hints for 7xx/9xx - Bill Garland's Nuclear ...

You first unscrew the male fitting and release the rubber hose from the bracket (generally just pull a Ushaped
sheet metal tab. Then you can unscrew the hose(s) from the caliper.
[Caveat:] If you run into problems, you can cut the metal line close to the nut and re-flare it
at the end using a new metric European (not Asian) fitting. Two new nuts could be taken off
of each short line you purchased and cut (available in 12" lengths.) The line has what is ISO 57.5
called an "ISO double flare". I remember that it can be duplicated with a normal flaring tool Degree
but takes a bit of talent and practice. It involves a two step procedure. You need a special Double
double flaring tool to do the lines - the normal single flare tool will not do the job. And even Flare
with the tool - it takes a bit of practice to get them to come out right consistently. It is a lot
easier to use the tool on the bench than it is under the fender of the car on the end of the
brake line. It is well worth spending a few hours with penetrating oil and careful working
back and forth of the nut than to try to repair a broken line. After replacement, the entire brake system will
require flushing/bleeding (Use pressure bleeder like Eezibleed).
Installation Tips for New Hoses. [Zee] Pretty straight forward. I found it good to
1. Place a plastic membrane under the fluid bottle cap for extra suction to prevent fluid from gravity
draining as fast while each old flex hose was loosened/disconnected. Open a bleed screw, block the
brake pedal down with a wood stick, then close bleeder—to stop fluid loss from the master cylinder
while lines are open.
2. It helped to loosen each end of the hose (fitings) to make sure they will let go. If one joint will not, you'll
be better off tending to that before loosening or removing any of the others. I didn't need to soak the
unions very long in penetrant [but see the cautions above about frozen fittings].
3. Unclip the ABS line (if you have ABS) from the flex hose. It will give you more room to work. Undo the
upper end of the hose before the lower end. This makes it easier to unscrew the lower end because
you can stand up the hose and rotate the thing.
4. You'll need two 14mm wrenches and an 11mm. Use quality flare wrenches to prevent rounding the
fittings.
5. Use a large catch basin and some cardboard under it on the floor. You won't expel a lot of fluid, but
this does leave a mess. [Art Benstein] Insert a sharpened golf tee in the end of the line or hose to
prevent fluid loss.
6. First remove the hose at the brake line end, then at the caliper side.
7. Think about a way to "fill" the new hose with brake fluid before bleeding that column of air into a
perfectly bled caliper. Even though you need to screw the lower end onto the caliper before joining the
top end to the flare nut hard line, you can leave the lower end loose, connect the top, then let gravity
bleed some brake fluid into the new hose to fil it just before tightening it to the caliper. It will minimize
the amount of air you will introduce to your system. Clean up the caliper area later with a shot of brake
cleaner.
Replacement Brake Lines. [Rob Bareiss] Volvos and
almost all European cars use the ISO 57.5 degree
"double flare" lines- the end flares out and back in. It
almost looks like a rivet. The fittings are European
(not Asian) metric. When sourcing new lines, it's
best to have the old lines in hand unless you're sure
what you're looking for. Dealers, most auto stores
and Internet Volvo aftermarket retailers stock
straight lengths of made-up brake lines as well as
the correct hoses. [Editor] The Volvo OEM lines are
Measuring Brake Line and Fitting Angles