Toyota 3R-B 1969, Repair Manual

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1-4 G E N E R A L I N F O R M A T I O N - General
T h e crankshaft thrust bearings a re located at the center main bearing, and are
of steel backed babbit metal •
T h e camshaft is of chilled casting, and the camshaft timing ge ar is of bakelite.
T h e camshaft is supported by five b earings, and these bearings a re of steel
backed white metal.
T h e exhaust valve head is of austenite heat resisting s te e l, and dual valve springs
a re utilized f o r both intake and exhaust v a lv e s .
T h e springs a r e made with irre gu la r pitch to prevent the valve surging.
T h e valve lifters a re installed with off-set from the center of the cam to s e r v e the
lubrication of the lifter and to prevent the uneven w e a r of the lifter.
T h e push rod s a r e made of steel pipe with the diameter of 9 mm (0.31 '*) , and
both ends of the pipe a re welded to the steel balls by butt welding.
Precauition
W henever any w ork is p erform e d on the c a r , special c a r e should be taken to
prevent scratching the body, fen d ers o r spoiling the seats. T o perform a satis­
factory w o r k , fen der c o v e r s o r seat c o v e r s must be used during the operation.
T h e use of S e r v i c e S p ecia l T o o ls must be emphasized as these tools a re so
designed to prevent damaging of the components, and also will quicken the w o r k .
During disassembling any components, it is essential that parts disassembled
from the c a r o r main components should be placed in sequence to facilitate the
final inspection, and assem bly. Certain mating parts should be marked before
disassembling from the main assembly to identify the mating position o r fo r baP
ancing with the main assem bly.
S e r v i c e T o r q u e Specification should be adhered w h e n ev er tightening the bolts
o r nuts.