Chevrolet 10 Series 1970 Service Manual page 281

LATCH PLATE
DIE BLOCK
TUBEX
\
STOP PLATE
F ig . 7 3 —F la rin g O p e ra tio n P o s itio n in g Tubing
two points in appropriate d irection , rep lace reta in er
sprin g and re -in s p e c t as outlined in this paragraph.
6 .
P la c e ste e l tube connector in hose fittin g and tighten
secu rely.
7. B leed a ll brakes as outlined in this section.
Hydraulic Brake Tubing (Figs. 71 thru 7 5 )
H ydraulic brake tubing used on a ll trucks is a double
la y e r fle x ib le steel, copper coated and tin plated tubing
which re s is ts co rro s io n and also stands up under the high
p ress u re s which are developed when applying the brakes.
In making up hydraulic brake pipes, it is im portant that
the ends o f the tubing be fla re d p ro p e rly fo r the co m p res­
sion couplings. Unless the tubing is p ro p e rly flared , the
c o u p l i n g s
w ill leak and
in e ffe c tiv e .
Th is safety ste e l tubing must be double-lap fla red at
the ends in o rd e r to produce a strong lea k -p ro o f joint.
The T o o l J-2185 must be equipped with the p rop er size
die block and upset fla r e punch fo r each size tubing to
fo rm the double-lap fla re .
The p ro p e r s iz e die blocks and upset fla r e punches are
as fo llo w s :
Tubing Size Die B lock
J-2185-27
3/16"
1/4" J-2185-28
J-2185-29
5/16"
Figu re 71 shows two p ieces o f tubing— one with a
sin g le-la p fla re " A " and the other with a double-lap
fla r e " B " . It w ill be noted that the sin g le-la p fla re splits
the tubing while the double-lap fla re shown in " B " is a
heavy, w e ll-fo r m e d joint.
The follow in g procedure should be follow ed in making
up hydraulic brake pipes:
1. Cut the tubing to the d esired length, using Tool
J-8000. Square o ff ends o f tube and ream sharp
edges with re a m e r tool p rovid ed on the tube cutter.
2. Install com pression couplings on tubing and dip end
The M aster Vac (fig s . 76 and 77) is a self-contained
hydraulic and vacuum unit fo r pow er braking, u tilizin g
m anifold vacuum and atm ospheric p ressu re fo r its pow er.
RAM GUIDE
RAM
the b r a k e s w ill become
Upset Finish
F la r e Punch F la re Punch
J-2185-3 J-2185-26
J-2185-37 J-2185-26
J-2185-26
J-2185-4
VACUUM POWER BRAKE UNITS
(1 0 -2 0 -3 0 SERIES)
GENERAL DESCRIPTION
LATCH PLATE
DIE
TUBE\
PLATE
F ig . 7 4 —F la rin g O p e ra tio n —First Flare
F ig . 7 5 —F la rin g O p e ra tio n —First and Second Flare
o f tubing to be fla re d in hydraulic brake fluid. This
lubrication resu lts in better form ation o f the fla re .
3. Select the c o r r e c t s iz e upset fla re punch. One end
o f this punch is hollowed out to gauge the amount o f
tubing n ecessary to fo rm a double-lap fla re .
4. Slip the punch into the tool body with the gauge end
toward the die blocks, install the ram and tap ligh tly
until the punch m eets the die blocks and they are
forced sec u re ly against the stop plate.
5. Draw latch plate nuts down tight to preven t tube from
slipping. Draw nuts down alternately beginning with
nut on closed side to prevent distortion o f plate.
6. Rem ove punch and ram .
back in tool body. Install ram and tap ligh tly until
face of punch contacts face of die blocks to com plete
fir s t fla r e operation.
7. Rem ove ram and punch.
8. Insert finish fla r e and ram in tool body and tap ram
until a good seat is form ed.
9. Blow tubing out with com pressed air.
The M a ster-V a c pow er brake unit p erm its the use o f
a low brake pedal as w e ll as le ss pedal e ffo rt than is
BRAKES 5-43
RAM GUIDE
RAM
R everse punch and place
CHEVROLET TRUCK SERVICE MANUAL