Chevrolet 10 Series 1970 Service Manual page 423

F ig . 131 — Rem oving Upper Seal
4. Attach vacuum hose to the adapter on the distributor
and start tester. In crease
reading reaches a m aximum value. T h is maximum
value w ill va ry , depending on the type "s p in n e r "
parts used, but w ill probably be above 3.8" hg.
5. A fte r this maximum
slow ly d ecrease the distribu tor speed until the v a c­
uum gauge hand fa lls back .1 " hg. The speed at which
this .1" hg. drop occu rs w ill be the approxim ate no
load governed speed.
to r rpm is half engine
adjustment.)
Installation—Engine Not Disturbed (A ll M odels)
1. Turn the ro to r about 1/8 turn in a clockw ise d ire c -
speed until the vacuum
reading has been reached,
(R em em ber that d istribu ­
rpm when making this
VACUUM HOLE
FIGURE 8 —VIEW SHOWING
USE OF PUNCH TO LOOSEN
LOWER SEAL BY DENTING
________ O NE SIPE________
F ig . 1 4 i— Loosening Lower Seal
tion past the m ark p reviou sly placed on the distribu ­
tor housing to locate roto r.
2. Push the distribu tor down into position in the blr
with the housing in a norm al "in s ta lle d " pos- '
(fig s. 19i and 20i).
NOTE: It may be
slightly to start gea r into mesh with camshaft
gea r, but ro to r should line up with the mark
when distribu tor is down in place.
3. Tighten the distribu tor clamp bolt snugly and connect
vacuum line. Connect p rim a ry w ire to c o il term in al
and install cap. A ls o
tension w ire s i f rem oved.
NOTE: It is im portant
w ires be installed in th eir p roper location in the
supports (fig . 21i).
T im e ignition as p revio u sly described under Tune-Up
4 .
in Section 6.
In stallation—Engine Disturbed (All M odels)
1. Locate No. 1 piston in firin g position by eith er of
two methods describ ed below.
a. Rem ove No. 1 spark plug and, with fin ger on plug
hole, crank engine until com pression is felt in the
No. 1 cylin der. Continue cranking until tim ing
m ark on crankshaft pulley lin es up with tim ing
tab attached to engine front co ver.
b. Rem ove ro ck er c o v e r (left bank on V -8 engines)
and crank engine until No. 1 intake va lve clo se s
and continue to crank slow ly about 1/3 turn until
tim ing m ark on pulley lines up with tim ing tab.
2. P osition distribu tor to opening in block in norm al
in stalled attitude (fig.
o f vacuum control unit.
3. P osition ro tor to point toward front of engine (with
distribu tor housing held in installed attitude), then
turn rotor cou n ter-clock w ise approxim ately 1/8 turn
m ore toward le ft cylin der bank and push distribu tor
down to engine cam shaft.
rotate rotor sligh tly until camshaft engagement is
felt.
W hile p ressin g fir m ly down on distribu tor housing,
4 .
ENGINE-ELECTRICAL 6Y-31
LOWER
SEAL
n ecessary to move rotor
install spark plug and high
that the spark plug
19i and 21i), noting position
It may be n ecessary to
CHEVROLET TRUCK SERVICE MANUAL