Brake Pipe Retainers; Double Lap Flaring; Hydraulic Brake L I N E S; Tubing - Chevrolet CHEVY VAN G10 SERIES Service Manual

BRAKES 5-6
N O T E : To assist the bleeding operation, a rawhide
m allet may be used to tap the caliper while fluid is
flowing.
6
. Remove brake bleeder w rench and hose from the bleeder
valve and repeat Steps 2 through
wheel cylinders.
7. Fill the m aster cylinder to th e level show n in Figure
8
. Install the m aster cylinder diaphragm and cover.
N O T E : In order to have a good surge of flu id at
the bleeder valve, the brake pedal should be pumped
up and pressure held before each opening of the
valve.
H Y D R A U LIC BRAKE LINES
Hydraulic Brake Hose
The flexible hoses w hich carry the hydraulic pressure from
the steel lines to the wheel cylinders are carefully designed and
co nstru cted to w ithstand all conditions o f stress and twist
w hich they encounter during norm al vehicle usage.
The hoses require no service o th e r than periodic inspection
for damage from road hazards or other like sources. Should
damage occur and replacem ent becom e necessary, the follow ­
ing procedure is to be follow ed.
Removal (Fig. 9)
1. Separate hose from steel line by turning double flare
connector o u t o f hose fitting using a back up w rench on
hose fitting.
2. Rem ove " U " shaped retainer from hose fitting and
w ithdraw hose from support bracket.
3. Rem ove hose to caliper bolt and remove hose.
Replacement (Fig. 9)
1. Install the hose to caliper using new gaskets. T orque the
m ounting bolt.
C A U T IO N : See "C a u tio n "
section.
2. Insert hose into fram e b racket or fram e crossm em ber—
this end o f hose will properly m ate in one direction only.
N O T E : The hose should enter the brakcet w ith a
slight tw ist of about 2 0 °.
3. Install " U " shaped retainer to secure hose in support
bracket.
4. Place steel tu be connector in hose fitting and tighten to
specifications. Use a back up w rench on the hose fitting.
C A U T IO N : See "C a u tio n "
section.
5. Bleed all brakes as outlined in this section.
BRAKE PIPE RETAINERS (Fig. 10)
R etainers are used to secure the brake pipes to the frame
and crossm em bers. This same retainer secures the fuel pipe in
some locations. T he retainer is held in place by b o lt and n u t or
sheet m etal screws.
6
on the remaining
8
.
on Page 1 of this
on Page 1 of this
Fig. 9 —Brake L in e S u p p o rt B racke t

Tubing

H ydraulic brake tubing is a double layer steel tubing w hich
resists corrosion and has the physical strength to stand up
u nder the pressures w hich are developed when applying the
brakes. In m aking up hydraulic brake pipes, it is im p o rtan t
th a t the proper flaring to o l be used to flare the ends of the
tubing for the com pression couplings.
C A U T IO N : When necessary to replace brake tu b ­
ing, always use special steel tubing which is designed
to withstand high pressure and resist corrosion.
O rdinary copper tubing
should not be used.
This safety steel tubing m ust be double-lap flared at the
ends in order to produce a strong leak-proof joint.
The Brake Tube Flaring Tool J-2185 (Fig. 11) is used to
form the double-lap flare.
The T ool m ust be equipped w ith the proper size die block
and upset flare punch for each size tubing to form the
double-lap flare.
The proper size die blocks and upset flare punches are as
follows:
T ubing Size Die Block
3 /1 6 " J-2 1 85-27
1 /4" J-2185-28
5 /1 6 " J-2 1 85-29
Figure 12 shows tw o pieces o f tubing, one w ith single-lap
flare " A " and the other w ith double-lap flare "B" . It will be
n o te d th a t the single-lap flare in " A " split the tubing while the
one show n in " B" is well-form ed and unb ro k en due to the
reinforcem ent o f the double wall.
The following procedure should be follow ed in making up
hydraulic brake pipes.

Double Lap Flaring

1. C ut the tubing to the desired length, using T ool J-8000.
is not satisfactory and
Upset Finish
Flare Punch Flare Punch
J-2 1 85-3
J-2 1 85-26
J-2185-37
J-2 1 85-26
J-2185-4 J-2185-26
C H E V Y V A N SH O P M A N U A L