Chevrolet 1977 light duty truck Service Manual page 398

Fig. 5-5--Typical Rear Hose Fittings
1. Procure the recom m ended
fitting nuts o f the correct size. (Outside diam eter of
tubing is used to specify size.)
2. Cut tubing to length. Correct length may be
determ ined by measuring old pipe using a cord and
ad ding 1 /8 " for each double flare.
3. D ouble flare tubing ends using a suitable flaring
tool such as J-23530. Follow instructions included in tool
set.
M ake sure fittings are installed before starting
second flare.
W A R N IN G : DOUBLE FLARING TOOL M U S T
BE USED AS SIN G LE
C A N N O T PRODUCE
E N O U G H TO HOLD
PRESSURE.
4. Bend pipe assembly to match old pipe using a
tubing bender. Clearance o f .75" must be m aintained to
all moving or vibrating parts.
BRAKE HOSES
Inspection
The flexible hydraulic brake hose which transmits
hydraulic pressure from the steel brake pipe on the
fram e to the rear axle and to the calipers should be
inspected every 4 months or 6,000 miles (heavy duty
emission vehicles), every 12 m onths or 7,500 miles (light
duty emission vehicles). The brake hose assembly should
be checked for road hazard dam age, for cracks and
chafing o f the outer cover, and for leaks and blisters. A
light and m irror may be needed
tubing and steel
FLARING TOOLS
A FLARE STRONG
T H E NECESSARY
for an adequate
inspection. If any o f the above conditions are observed
on the brake hose, it will be necessary to replace it.
Front Brake Hose
R em o val (fig s . 5 -2 th ru 5 -4 )
1. Raise vehicle on hoist.
2. Clean dirt and foreign material from both hose
end fittings.
3. Disconnect brake pipe from hose fitting using a
back-up wrench on fitting. Be careful not to bend frame
bracket or brake pipe. It may be necessary to soak the
connections with p enetrating oil.
Remove " U " clip from female fitting at bracket
4.
and remove hose from bracket.
5. Remove bolt from caliper end o f hose. Remove
hose from caliper, and discard the two copper gaskets on
either side of fitting block.
In s ta lla tio n
1. Use new copper gaskets on both sides o f fitting
block, wet bolt threads with brake fluid, then with fitting
orientation flange engaged with the caliper orientation
ledge on JB8 and JF9 (hose located in caliper gate on all
except JB8 and JF9), fasten hose to caliper; torque to
specifications.
2. With weight o f vehicle on suspension, pass
female fitting through frame or fram e bracket. Fitting
fits the bracket in only one position. With least am ount
of twist in hose, install fitting in this position. There
should be no kinks in hose.
3. Install " U " clip to female fitting at frame
bracket.
Attach brake pipe to hose fitting using a backup
4.
w'rench on fitting; torque to specifications.
5. Inspect to see that hose doesn't make contact
with any p art of suspension. Check in extreme right
hand and extreme left h and turn conditions. If hose
makes any contact, remove and correct.
6. Bleed brake system.
7. Lower vehicle from hoist.
Rear Brake Hose
R em o val
1. Raise vehicle on hoist.
2. Remove all three brake pipes from hose, two at
junction block and, with the use o f a back-up wrench,
one on the female fitting at bracket. Be careful not to
bend bracket or pipes; use penetrating oil if necessary.
3. Remove " U " clip and take female fitting out of
bracket (fig. 5-5).
4. Observe position at w'hich junction block is
mounted to the axle. W hen installing new hose be sure
this junction block is in the same position.
5. Remove bolt attaching junction block to axle.
In s ta lla tio n
1. T hread both rear axle pipes into junction block.
2. Bolt junction block to axle and then torque rear
pipes into block.
3. Pass female end o f hose through bracket;