Chevrolet DB90 Series, Руководство по обслуживанию

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S ec. 10-195
drive a x les should equal the sum of the circu m fer­
e n ce s of the 4 tir e s on the rear of the tandem a x le s.
T h is precaution is n e c e ssa r y to prevent e x c e ssiv e
w ear from slippage. If th ere is a third differential
betw een th ese two drive a x le s, d isregard th is r e c ­
om m endation. L ikew ise it is to be disregarded for
s e m i-tr a ile r tandem t ir e s b ecau se th ese a r e on
fr e e -r o llin g w h eels.
SYNTHETIC TUBES AND FLAPS
TUBES CHAFED OR PINCHED
BY FABRIC BREAKS
Tubes may fa il as a re su lt of being chafed or
pinched by fabric breaks in sid e the tir e . The d ir e c ­
tion and shape of the tube in ju ries have rather
c lo s e ly follow ed the pattern of the fabric breaks.
A tir e does not n e c e ssa r ily go flat im m ediately
when a fabric break o ccu rs on the in sid e of the tir e
b eca u se it may take som e tim e for the injury to
chafe com pletely through the tube.
TUBES DAMAGED BY
MISMOUNTED FLAPS
The tube may becom e chafed by a fold at the
edge of the flap. In mounting tir e s requiring flap s,
it is e sse n tia l that the flap s be properly centered
betw een beads to prevent fold s or w rin k les. Flaps
which have once becom e tw isted , cre a se d , or folded
o v er at ed g es, should not be used again.
TUBES AND CASINGS DAMAGED
BY FOREIGN MATERIALS IN CASINGS
Any foreign m aterial between the casin g and
tube w ill cau se a chafing action. In tim e, one or
both w ill becom e badly dam aged and fa il. The r e ­
su lt of grit, p eb b les, or other hard substances which
b ecom e embedded in the tube w all, w ill chafe tube
and finally cau se fa ilu re.
TUBES STRETCHED AND CREASED
When a tube i s la r g e r than the in sid e of the
WHEELS AND TIRES
T-8305
Figure 14—Im proper Tube Inflation
casin g it has b ecom e stretch ed and can becom e
c r e a se d . C reasin g can a lso happen to a new tube
of proper s iz e when in co rrectly mounted. If the
c r e a s e o ccu rs in the flexing area of the tir e , the
resu ltin g additional th ick n ess o f the tube where
folded c a u se s a hinging action which cuts the tube
and frequently dam ages the fabric - resu ltin g in a
c o stly failu re.
CREASES CAUSED BY
REMOUNTING USED TUBES
Tubes usually undergo som e str etch or growth
in s e r v ic e . T his i s p a rticu la rly true of truck tubes
b e ca u se of the high tem p eratu res which develop.
When a used tube is rem ounted in a new, or nearly
new tir e , a folded condition w ill usually resu lt,
and eventually w ill ca u se both tube and tir e to fa il.
Figure 15—Proper Tube Inflation
CHEVROLET SERIES 70-90 HEAVY DUTY TRUCK SHOP MANUAL SUPPLEMENT