Toyota 3R-B 1969, Руководство по ремонту

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3-20 E N G I N E - Maior S e r v i c e
gines and 09222-30010 fo r 5R en­
gine.
A f t e r installing the bushing, hone
the bushing in a pin hole honing
machine o r a re a m e r to obtain
p r o p e r fitness with the piston pin
and the bushing.
T h e piston pin fitness can be d e­
termined by pushing in the pin into
the bushing with the thumb applying
engine oil onto the piston pin.
Connecting Rod B e arin g
T h e connecting rod bearings a r e in­
se rt type, m icro-precision finished
with high quality and close to le ra n c e .
Do not scra p e o r insert any shim,
and also do not file o r lap the b e a r ­
ing cap o r bearing to obtain the spe­
cified clea ran ce.
1 . Check the bearing fo r p o or con­
tact, w orn thin, partially melted
o r heavily s c o r e d .
If n e c e s s a ry , rep la ce the b e a r in g s .
2. R em ov e any deposit of oil, dirt
o r foreign matter from the crank
pin journals, and also from the
connecting rod b ea rin gs.
3. P la c e a piece of the Plastigage
on the crank pin journal fo r the
full width of the b earing, and
parallel to the crankshaft avoiding
the hole in the journal.
F i g . 3-33 P la cin g P lastigage V4684
4 . Installing the connecting rod b e a r ­
ing and cap, tighten the nuts to
specified torque. Do not turn the
crankshaft while the Plastigage is
in p la c e .
Specified torque:
6.0 ~ 7.0 m-kg (43 ~ 51ft-lbs)
5. R em ov e the c a p , and check the
width of the Plastigage with the
Plastigage c o v e r scale.
Read the widest point in o r d e r to
obtain the minimum clearan ce.
Read the difference between the
two readings at both sides of the
P la s t ig a g e .
6. If the clearan ce exceed s 0.08 mm
(0 .0031" ) , the bearings must be
replaced with an under size b e a r ­
ings, and grind the crank pin jo u r­
nals to obtain the specified c le a r ­
ances .
B e arin g clearance:
0.025 ~ 0.060 mm
(0.0010 0 .0 0 2 4 ")
C leara n ce limit:
0.080 mm (0 .0 0 3 1 ")
7. If the bearings a r e to be re p la c e d ,
select the p r o p e r size bearings
r e fe r r in g the following table.
Connecting rod bearings:
F o r 3 R - B & 3 R - C engines:
S T D :
B e arin g thickness:
1.508 ~ 1.518 mm
(0.0594 ~ 0 .0 5 9 7 ")
C rank pin finished diameter:
54.985 ~ 55.000 mm
(2.1648 ~ 2 .1 6 5 4 ")
U / S -0 0 2 :
B e arin g thickness:
F ig . 3-34 Measuring Oil V4685
C learance