Specifications

(5) Tighten the engine cylinder head bolts in
sequence according to the following procedure (Fig.
34):
a. The threads and underside heads of the bolts
should be lubricated. Use the cylinder head align-
ment studs tool number VM-1009. Position the heads
on the block and secure with the ten large center
bolts and spacers (clamps), finger tight only.
b. Ensure that the various clamps are installed
correctly and the head gasket remain in their proper
position, completely covered. Then, lubricate and
install the eight small bolts, also finger tight.
(6) Loosen assembly oil feed line for rocker arm
assemblies
(7) Install the intake and exhaust manifolds with
new gaskets, partially tightening the nuts to a max-
imum of 5 N·m (44 in. lbs.). This will align the heads
(refer to Group 11, Exhaust System and Intake Man-
ifold for the proper procedures). Install lift eye and
brake vacuum tube at this time.
(8) Then, tighten the 12mm bolts with special tool
VM-1019 in the following manner:
(9) 1st Phase: Tightening Head Bolts (Fig. 34).
Central bolts (A-L): Tighten all bolts, starting with
bolt A then B-C-D-E-F-G-H-I-L, to 30 N·m. Repeat
the operation with the same torque. Following the
same sequence rotate each bolt through an angle of
70° using angle torque tool. Then rotate the bolts an
additional 70° following tightening sequence.
(10) Then, tighten the 14mm bolts with special
tool VM-1018 in the following manner:
(11) Side bolts (M1-M2): Tighten M1 bolts to 30
N·m, then rotate them 85° (65). Tighten M2 bolts to
30 N·m, then rotate them 85° (65).
(12) 2nd Phase: After 20 minutes of engine oper-
ation at operating temperature, allow engine to cool
down completely. Then retorque the head bolts as fol-
lows:
(13) Central bolts A-L: Starting from bolt A,
slacken and retorque it immediately to 30 N·m + 65°.
Rotate the bolt an additional 65°. Then proceed in
the same way, bolt by bolt, following alphabetical
order, as indicated.
(14) Side bolts M1-M2: Without slackening ,
torque bolts M1 then bolts M2 to 90 N·m (66 ft. lbs.).
(15) Tighten intake nuts to 30 N·m (22 ft. lbs.) and
exhaust manifolds nuts to 30 N·m (22 ft. lbs.) speci-
fied torque after completing Phase 2.
(16) If the engine cylinder head is to be replaced
and the original valves used, measure the valve stem
diameter. Only standard size valves can be used with
a service replacement engine cylinder head unless
the replacement head valve stem guide bores are
reamed to accommodate oversize valve stems.
Remove all carbon buildup and reface the valves.
(17) Tighten oil feed lines for rocker arm assem-
blies and oil pressure switch to 13 N·m (112 in. lbs.).
(18) Install push rods and rocker arm assemblies,
tighten nut to 29.4 N·m (264 in. lbs.).
(19) Install fuel injectors use tool VM-1012 (refer
to Group 14, Fuel System).
(20) Install valve cover, tighten nuts to 14.7 N·m
(132 in. lbs.).
Fig. 34 Engine Cylinder Head Bolt Tightening Sequence
9 - 52 ENGINE NS/GS
REMOVAL AND INSTALLATION (Continued)