Chevrolet 10 Series 1968, Service Manual

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WHEELS AND TIRES 10-15
Installing Synthetic Tubes
1. Before installing tube in tire, clean inside of casing
thoroughly.
2. Insert tube in tire and inflate until it is nearly
rounded out.
3. Inspect rim for rust scale and bent flanges--clean
rust scale and straighten flanges where necessary.
4. Using a brush or cloth swab, apply a solution of
neutral vegetable oil soap to the inside and outside of
tire beads and also to the rim side of the tube. Do
not allow soap solution to run down into tire.
5. When mounting tire and tube on a drop center rim,
follow the standard procedure. Be sure tire is cen­
tered on rim so that beads are out of rim well before
inflating. Do not allow tire to hang loosely on wheel
while inflating.
6
. Center valve and pull it firm ly against the rim. Hold
in this position and inflate until tire beads are firm ly
seated on rim against flanges.
7. Completely deflate tire by removing valve core.
8 . Reinflate tire to recommended pressure.
CA U TIO N : When tube and flap are not properly
lubricated and mounted, they will stretch thin
in the tire bead and rim region. This will cause
premature failure.
Tubeless Tires
Tubeless tires mounted on one piece full drop center
rims are standard on some Chevrolet trucks. These
tires have a safety inner liner which if punctured, tends
to cling to the penetrating object forming a partial seal
until the object is removed from the tire.
The mounting and demounting of tubeless truck tires
will present no problem when a rubber lubricant, such as
Ru-Glyde or equivalent is applied to tire beads and rim
flanges. Ru-Glyde or equivalent in addition to materially
assisting in mounting and demounting also prevents rust­
ing at the tire sealing area and thus prevents tires from
adhering to the wheel.
Demounting and Mounting
A ll tubeless tires used on Chevrolet trucks with the
exception of the 7.75-15 and 6.50-16 sizes should be de­
mounted and mounted as described in this section. The
7.75-15 and 6.50-16 sizes may be demounted using
present tire machines or standard tire irons following
the same procedure employed in servicing tube type
tires.
C A U TIO N : A hammer, or tools with sharp
edges, should never be used to demount or mount
tubeless tires as damage to rim flange or tire
sealing bead may result.
Inspection for Leaks
1. With wheel assembly removed from vehicle, inflate
the tire to recommended operating pressure.
2. Check for leaks at rim bead by placing wheel and tire
horizontal and allowing water to stand in groove be­
tween rim and tire. Check for large leaks by lower­
ing assembly into water tank or running water over
tire.
Demounting (all except 7 .75-15 and 6.5 0 -1 6 tires)
1. Remove valve core to completely deflate tire. With
tire lying flat on floor, loosen beads from rim seats
by walking around on tire with heels at points close
to rim. With wide side of rim down, apply tire lu­
bricant to top bead. With stops toward rim, insert
spoon ends of two tire irons about 10" apart. While
standing on tire to hold bead in gutter, pull one tool
toward center of rim (fig.
20
).
2. Hold one iron in position with foot and pull second
iron toward center of rim. Progressively work bead
off rim, taking additional bites if necessary (fig. 21 ).
Fig . 19—C h eckin g Side Ring for Bind on Rim Fig. 20—Inserting Tire Iron to Lift Bead
CHEVROLET TRUCK SERVICE MANUAL