Chevrolet 70 Series 1970, Service Manual

Page: 671 / 841

FUEL TANK AND EXHAUST 8-4
Figure 8—Installation of Teflon Hose
to Insure Proper Bend ■ Radius
When in stallin g eith er rigid or flex ib le fuel
lin e s with threaded couplings, tighten nuts only
enough to prevent leakage and provide a secu re
connection. W here p o ssib le , a back-up w rench
should b« u sed to prevent tw isting or e x c e s s s t r e s s
on fuel lin e . DO NOT OVER-TIGHTEN.
Fuel lin e s should be in sp ected o cca sio n a lly
for lea k s, kinks, or dents. Dented, kinked, or
Figure 9—Proper Installation of Teflon Hose
crack ed fuel lin e s m ust be rep laced . If seep age at
connections cannot be co rrected by tightening,
fittin g s and lin e s m ust be rep laced .
If contam inants a re found in fuel filt e r s , or
evidence of clogging is indicated, disconnect s u s ­
p ected lin e at both ends and blow out with com ­
p r e s s e d a ir . If p a ssa g e cannot be c le a r e d of ob­
stru ctio n s, rep la ce with new lin e . A clogged str a in ­
er on tank pickup pipe can re su lt in fuel starvation.
Clean or rep lace a s required. DO NOT om it strainer.
When replacing a flex ib le fuel lin e, be su re
h ose is properly located to p revent chafing against
fram e m em b ers. F uel lin e reta in ers should be
p o sitio n ed p rop erly on fuel lin e s to a ssu r e se c u r e
support yet not resu lt in lin e con striction . Cracked,
corroded, or bent r e ta in ers should be replaced.
TEFLON HOSE REPLACEMENT
D isa ssem b ly
R efer to figu re 7 for sectio n a l view of teflon
h o se.
1. U n screw and rem ove the nipple.
2. Slide the sock et back on the h o se by tapping
again st a flat su rfa ce.
3. R em ove the s le e v e from the teflon hose
with p lie r s .
A ssem b ly
R efer to figu re 7 for sectio n a l view of teflon
h o se.
1. Wrap h ose with m asking tape at cu t-off
point and cut squarely to length through the taped
a rea u sin g a sharp cu t-off w heel or a fin e-tooth ed
hacksaw .
2. R em ove tape and trim any lo o se w ir e s flush
with the tube stock . Any b u rrs on the bore of the
tube sto ck should be rem oved with a knife. Som e­
tim e s w ire braid w ill tend to "neck down" on one
end and "flare out" on the opposite end. T h is is a
c h a r a c te r istic of w ire braid hose and can be used
to an advantage in the a ssem b ly of the fittin g s (item
1, fig- 7).
3. Slip two so c k ets b a ck -to-b ack ov er the
"neck down" end of the h o se. P o sitio n the so ck ets
approxim ately 3 in ch es from each end (item 1,
fig . 7).
4. Mount nipple hex in a v is e . Work the hose
b ore over the nipple to s iz e the tube and aid sep a r­
ating the braid from the teflon inner tube. Rem ove
the h ose from the nipple (item 2, fig . 7).
5. P ush the s le e v e over the end of the inner
tube and under the w ire braid by hand. Com plete
p osition in g of the s le e v e by pushing the h o se end
again st a flat su rface (item 3, fig . 7).
6. V isu ally in sp ect to s e e that the tube stock
butts against the in sid e shoulder of the s le e v e . Set
the s le e v e barbs into the teflon tube by pushing a
CHEVROLET SERIES 70-90 HEAVY DUTY TRUCK SHOP MANUAL