Chevrolet 10 Series 1970, Руководство по обслуживанию

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CLUTCHES AND TRANSMISSIONS 7-43
fr o m ro llin g . The pointer on the indicator quadrant
should line up p ro p e rly with the range indicators in all
ranges.
OIL LEAKS
B e fo re attem pting to c o r r e c t an o il leak, the actual
sou rce of the leak must be determ ined. In many cases,
the sou rce o f the leak can be d eceivin g due to "w in d
flo w ” around the engine and transm ission.
The suspected a rea should be wiped clean of a ll o il b e­
fo r e inspecting fo r the source of the leak. Red dye is
used in the tran sm ission o il at the assem bly plant and
w ill indicate if the o il leak is fro m the transm ission.
The use of a "b la c k light” to identify the o il at the
source of leak is also helpful. Com paring the o il from
the leak to that on the engine o r tran sm ission dip stick
(when view ed by black light) w ill determ ine the source
of the leak.
O il leaks around the engine and tran sm ission are gen­
e r a lly c a r r ie d toward the r e a r of the car by the a ir
stream . F o r exam ple, a tran sm ission " o i l f i l l e r tube to
case leak” w ill som etim es appear as a leak at the r e a r
of the transm ission. In determ ining the source of an oil
leak it is most helpful to keep the engine running.
POSSIBLE POINTS OF OIL LEAKS
1. TRANSM ISSION O IL P A N L E A K
a. Attaching bolts not c o r r e c tly torqued.
b. Im p ro p erly in stalled o r damaged pan gasket.
c. O il pan gasket mounting face not flat.
2. R E A R E XTEN SIO N L E A K
a. Attaching bolts not c o r r e c tly torqued.
b. R ea r seal assem bly - damaged o r im p ro p erly
installed.
c. Gasket sea l - (extension to case) damaged or
im p ro p erly installed.
d. Porou s casting.
3. CASE L E A K
a. F ille r pipe " O ” rin g seal damaged o r m issing;
m isposition o f f i l l e r pipe bracket to engine -
" load in g'' one side of " O ” ring.
b. M odulator assem bly " O ” ring seal - damaged or
im p ro p e rly installed.
c. G overn or c o ver, and " O ” rin g seal - damaged,
loose; case face leak.
d. Speedo gea r - " O ” rin g damaged.
e. Manual shaft seal-dam aged, im p ro p e rly installed.
f . Line p ressu re tap plug - stripped, shy s e a le r
compound.
g. P ark in g pawl shaft cup plug - damaged, im prop­
e r ly installed.
h. Vent pipe (r e fe r to Item 5).
i . Porou s case.
4. F R O N T END L E A K
a. Front seal - damaged (check con verter neck fo r
nicks, e tc .,a ls o fo r pump bushing moved forw ard ).
b. Pump attaching bolts and seals - damaged, m is s ­
ing, bolts loose.
c. C on verter - leak in weld.
d. Pump " O ” rin g sea l - damaged. (A ls o check
pump gro o ve and case b o re .)
e. Porou s casting (pump o r case).
5. O IL COMES OUT V E N T P IP E
a. T ra n sm ission o v e r -fille d .
b. W a ter in oil,
c. Pump to case gasket m ispositioned.
d. F oreign m a teria l between pump and case, o r b e­
tween pump c o v e r and body.
e. Case - porous, pump fa ce im p ro p e rly machined.
f . Pump - shy of stock on mounting fa ces, porous
casting.
CASE POROSITY—REPAIR
T ran sm ission leaks caused by aluminum case p o ro sity
have been su ccessfu lly re p a ire d with the tran sm ission in
the veh icle by using the follow in g procedure.
1. Road test and b rin g the tran sm ission to operating
tem perature.
2. R aise the car and, with the engine running, locate the
source of the leak. Check fo r leaks in a ll op erat­
ing positions.
NOTE: The use of a m ir r o r w ill be helpful in
finding leaks.
3. Shut off engine and thoroughly clean area with a s o l­
vent and a ir dry.
4. Using the instruction of the m anufacturer, m ix a suf­
fic ie n t amount of epoxy cement, part #1360016, to
make the rep a ir.
5. W hile the tran sm ission is s till hot, apply the epoxy
to the area, making certain that the area is fu lly
covered.
6. A llo w epoxy cem ent to d ry fo r three hours and r e ­
test fo r leaks, as outlined in Steps 1 and 2.
OIL PRESSURE CHECK
W ith Car Stationary
T ran sm ission o il p ressu re gauge and engine tachom e­
te r should be connected and the o il p ressu res should
check as follow s:
1. P re s s u re s (P S I) indicated below are at 0 output
speed with the vacuum modulator tube disconnected
and with engine at 1200 rpm.
Approxim ate
Altitude of Check
(F t. Above
Sea L e v e l)
D rive
Neutral
Park
L -6 and
V -8 R e v e rs e
L I o r L2
0
139
139 250
2000 139 139 235
4000 139 139
221
6000 132 134 203
8000 125 129
195
10000 117 123 184
12000 110 118 173
14000 104 113 163
2. P re s s u re s (P S I) indicated below are at 0 output
speed with the vacuum m odulator tube connected,
and with sufficient engine speed to maintain 16 inches
Hg absolute m anifold p ressu re.
CHEVROLET TRUCK SERVICE MANUAL