Nissan PULSAR N13 Series / ASTRA LD Series. Manual — part 12

Engine

49

Dismantled view of the camshaft housing and

components.

(10) If the measurement is not within Specifica-

tions, check the retaining plate and the retaining plate
groove in the camshaft for wear or scoring after
dismantling. Renew the defective parts as necessary
on assembly.

(11) Disconnect the lower radiator hose and drain

the cooling system.

NOTE: If the coolant is to be reused, drain
the coolant into a clean container.

(12) Remove the bolts securing the camshaft

drive belt inner cover to the camshaft housing.

(13) Remove the cylinder head bolts in the re-

verse order of the tightening sequence, backing off
each bolt a quarter of a turn then half a turn at a time
until the bolts are loose.

NOTE: Do not loosen the cylinder head
bolts while the engine is warm as distortion
of the cylinder head could result.

(14) Remove the cylinder head bolts and lift the

camshaft housing from the cylinder head.

(15) The rocker arms, thrust pads and tappet

assemblies can now be removed from the cylinder
head. Number a rack from 1 to 8 and keep each
assembly in order so that they can be returned to their
original positions.

(16) From the distributor drive end of the cam-

shaft housing, remove the bolts securing the camshaft
retaining plate to the camshaft housing and remove
the retaining plate.

(17) Withdraw the camshaft from the camshaft

housing taking care to support the camshaft to avoid
scoring the inner surfaces of the camshaft bearings.

(18) With a pointed drift, tap a small hole in the

front face of the oil seal. Insert a self tapping screw in
the hole and using a pair of pliers, pull on the screw
to remove the oil seal from the housing. Discard the
oil seal.

TO CLEAN AND INSPECT

(1) Wash all parts in cleaning solvent and dry

with compressed air. Ensure that all oil ways in the
camshaft and rocker arms are free from obstruction.

(2) Check the camshaft lobes, the rocker arms.

the thrust pads and the tappet assemblies for pitting
and wear. The tappet assemblies are non-serviceable
and should be renewed as an assembly if wear is
apparent or internal damage is suspected.

(3) Support the camshaft at each end on Vee

blocks and using a dial gauge with its plunger bearing
on the centre journal, rotate the camshaft and check
for bend.

(4) Using micrometers, measure the outside of

each camshaft journal and the inside of each camshaft
tunnel in the camshaft housing. Compare these mea-
surements to Specifications and renew defective parts
as necessary.

(5) Check the retaining plate and the retaining

plate groove in the camshaft for wear and scoring.
Renew defective parts as necessary.

Dismantled view of the valve operating components

.

TO INSTAL

Installation is a reversal of the removal procedure

with attention to the following points:

(1) Lubricate the lip of a new oil seal with engine

oil and position the seal squarely in the camshaft
housing. Ensure that the lip of the seal faces towards
the inside of the camshaft housing. Tap around the
edge of the seal with a soft faced hammer until the seal
is fully seated in the recess in the camshaft housing.

(2) Apply clean engine oil to the camshaft bear-

ings and camshaft journals. Insert the camshaft into
position taking care not to damage the bearings with
the edges of the cam lobes or journals.

(3) Apply engine oil to the camshaft retaining

plate and position it in the groove in the camshaft.
Install the retaining bolts and tension the bolts to the
specified torque.

50

Engine

(4) Ensure that the tappet assemblies are full of

clean engine oil and insert the tappets in their
respective bores in the cylinder head. Install the thrust
pads to the top of each valve assembly ensuring that
they are returned to their original location.

(5) Coat the contact surfaces of the rocker arms

with molybdenum disulphide grease and install the
rocker arms to their original locations on the cylinder
head.

(6) Clean the mating surfaces of the camshaft

housing and cylinder head. Apply a bead of Loctite
515 to the cylinder head and camshaft housing mating
surfaces. Take care that no sealant is forced into the
oil passages and install the camshaft housing to the
cylinder head.

(7) Install new cylinder head bolts and lubricate

the bolts and washers with oil.

(8) Apply an initial torque to the cylinder head

bolts of 25 Nm in the correct sequence as shown in
the illustration under the Cylinder Head heading.
Further tighten the head bolts in the correct sequence,
in three separate 60 degree stages. Refer to Specifica-
tions.

(9) Install the bolts securing the camshaft

drive
belt inner cover to the camshaft housing.

(10) Install the camshaft timing gear to the cam-

shaft ensuring that it is correctly located. Tighten the
camshaft timing gear retaining boll to the specified
torque.

(11) Install and adjust the camshaft drive belt as

described under the previous heading.

(12) Install the distributor. Refer to the Fuel and

Engine Management section.

(13) Connect the lower radiator hose and fill the

cooling system with the required coolant. Refer to the
Cooling and Heating Systems section if necessary.

(14) Start and run the engine until normal oper-

ating temperature is attained and tighten the cylinder
head bolts another 30-50 degrees in the correct
sequence, ensuring that the tension does not exceed
135 Nm.

TO RENEW CAMSHAFT OIL SEAL,
CAMSHAFT INSTALLED

(1) Remove the camshaft drive belt from the

camshaft timing gear as described under the previous
heading.

(2) Remove the camshaft housing top cover

retaining bolts, remove the cover and discard the
gasket.

(3) Use an open end spanner to hold the cam-

shaft between the inlet and exhaust lobes of number
four cylinder and remove the camshaft timing gear
retaining bolt and the camshaft timing gear.

(4) With a pointed drift, tap a small hole in the

front face of the oil seal. Insert a self tapping screw in
the hole and using a pair of pliers, pull on the screw
to remove the oil seal from the housing.

(5) Clean the seal recess and the camshaft sea!

running surface.

(6) Lubricate the lip of a new oil seal with engine

oil and slide the seal over the camshaft. Ensure that
the lip of the seal faces towards the inside of the
camshaft housing. Tap evenly around the edges of the
seal until it is fully seated in the camshaft housing.

(7) Install the camshaft timing gear to the cam-

shaft, ensuring that it is correctly located. Tighten the
camshaft timing gear retaining bolt to the specified
torque. Do not allow the camshaft to rotate while
tightening the bolt.

(8) Install and adjust the drive belt as described

under the previous heading. Ensure that the timing
marks are aligned.

(9) Install the camshaft housing top cover using a

new gasket. Tighten the retaining bolts to the specified
torque.

7. CYLINDER HEAD

Special Equipment Required:

To Dismantle and Assemble — Valve spring com-
pressor

To Inspect — Dial gauge and straight edge
To Install — Drive belt adjusting tool

TO REMOVE AND INSTAL

NOTE: Due to the high residua! pressure
within the fuel system, it will be necessary to
depressurize the system before removing any
fuel supply components. Refer to the Fuel
and Engine Management section for the
correct procedure.

Allow the engine to cool prior to the

removal of the cylinder head to prevent
possible distortion of the cylinder head.

(1) Disconnect the negative battery terminal and

remove the nuts securing the earth wires to the
cylinder head bolts.

(2) Remove the camshaft drive belt as previ-

ously described.

(3) Disconnect the lower radiator hose and drain

the cooling system. Refer to the Cooling and Heating
Systems section if necessary.

(4) Remove the alternator adjusting bracket

mounting bolt and insulating washers from the inlet
manifold. Loosen the adjusting bolt at the alternator
and slide the bracket away from the cylinder head.

(5) Disconnect the upper radiator hose, coolant

by-pass hose and the heater hose from the thermostat
housing and on 1.6 liter models, the coolant hoses
from the inlet manifold.

(6) Disconnect the electrical connectors from the

throttle body, fuel injectors, coil, distributor and on
1.8 liter models, the MAT sensor.

(7) Disconnect the oxygen sensor wiring connec-

tor and remove the wiring connectors from the

Engine

51

coolant temperature sensor and temperature sender
switch located in the thermostat housing.

(8) Remove the bolt securing the wiring clamp

to the rear of the manifold and maneuver the wiring
away from the cylinder head and the inlet manifold.

(9) Disconnect the throttle cable and on auto-

matic transaxle models, the kickdown cable from the
throttle body linkage.

(10) Remove the bolls securing the throttle cable

bracket to the inlet manifold and place the bracket
and cable(s) to one side.

(11) Mark the fuel supply and return hoses to

ensure correct installation and disconnect the hoses
from the fuel rail or throttle body. Plug the hoses to
prevent the loss of fuel or the entry of dirt.

(12) Mark the vacuum hoses connected to the

inlet manifold and throttle body to ensure correct
installation and disconnect the hoses.

(13) Remove the nuts securing the engine pipe to

the exhaust manifold and separate the pipe from the
manifold.

(14) Remove the oxygen sensor from the exhaust

manifold. Refer to the Fuel and Engine Management
section if necessary.

(15) Remove the distributor and coil as described

in the Fuel and Engine Management section.

(16) Disconnect the engine breather hoses from

the camshaft housing and camshaft housing top cover.

(17) Remove the bolts retaining the top cover to

the camshaft housing and remove the top cover.

(18) Using an open end spanner, hold the cam-

shaft between the inlet and exhaust lobes of number
four cylinder and remove the camshaft timing gear
retaining bolt and the camshaft timing gear.

(19) Remove the bolts securing the camshaft

drive belt inner cover to the camshaft housing.

(20) Loosen the cylinder head bolts in the reverse

order of the tightening sequence, backing off each bolt
a quarter turn then half a turn at a time until the bolts
are loose.

NOTE: Do not loosen the head bolts while
the engine is warm as distortion of the
cylinder head could result.

(21) Remove the cylinder head bolts and lift the

camshaft housing from the cylinder head.

(22) Remove the cylinder head and gasket from

the cylinder block.

Installation is a reversal of the removal procedure

with attention to the following points:

(1) Thoroughly clean the gasket surfaces of the

cylinder head, cylinder block and camshaft housing
and check all mating surfaces with a straight edge.
Ensure that all the oilways are clean and free of any
foreign material and lightly oil all operating parts with
engine oil.

(2) Install new gaskets throughout during

assem-
bly.

View of the cylinder head showing the bolt tightening

sequence.

(3) Ensure that the cylinder head and gasket are

located correctly on the dowels on the cylinder block
face. The head gasket is marked TOP to aid in correct
installation.

(4) With the cylinder head and gasket in posi-

tion on the cylinder block, apply an even smear of
Loctite 515 to the cylinder head and camshaft housing
mating surfaces. Take care that no sealant is forced
into the oil passages.

(5) Install new cylinder head bolts and lubricate

the bolts and washers with engine oil,

(6) Apply an initial torque to the cylinder head

bolts of 25 Nm in the sequence shown in the
illustration. Further tighten the head bolts in the same
sequence in three separate 60 degree stages. Refer to
Specifications.

(7) Install the bolts securing the camshaft drive

belt inner cover to the camshaft housing. Install the
camshaft timing gear and tighten the retaining bolt to
the specified torque.

(8) Install and adjust the camshaft drive belt as

previously described.

(9) Install the distributor, coil and oxygen sensor

as described in the Fuel and Engine Management
section.

(10) Using a new gasket, connect the engine pipe

to the exhaust manifold flange, coat the nuts with an
anti-seize compound and install and tighten the nuts
to
the specified torque.

(11) Connect all hoses and electrical wiring dis-

connected during the removal of the cylinder head.
Ensure that all the hoses are returned to their original
locations.

(12) Connect the throttle cable and where appli-

cable, the kickdown cable. Adjust the cables as
described in the Fuel and Engine Management section
and the Automatic Transaxle section.

(13) Check the engine oil for correct level on the

dipstick and for dilution. Change the engine oil and
filter if necessary.

(14) Fill the cooling system as described in the

Cooling and Heating Systems section.

(15) Start the engine and check for oil or water

52

Engine

leaks and rectify as necessary. Check and if necessary
adjust the ignition timing as described in the Engine
Tune-up section.

(16) When the engine has reached normal oper-

ating temperature, tighten the cylinder head bolts
another 40-50 degrees in the correct sequence shown
in the illustration, ensuring that the tension does not
exceed 135 Nm.

TO DISMANTLE

(1) Remove the cylinder head as previously

described.

(2) Remove the thermostat housing and sealing

ring from the cylinder head.

(3) Remove the nuts securing the inlet and

exhaust manifolds to the cylinder head and remove
the manifolds. Discard the gaskets.

(4) Lift the rocker arm and thrust pad from the

top of each valve assembly, keeping them in order for
assembly to their original locations.

(5) Slide each hydraulic tappet from its bore in

the cylinder head, also keeping them in order for
assembly to their original locations.

(6) Before removing the valves the deposits in

Installed view of the cylinder head oil pressure relief

valve.

the combustion chambers should be removed. Care
should be taken not to damage the cylinder head
gasket face.

(7) Using a valve spring compressor, compress

each spring in turn. Remove the split retaining collets
and slowly release the compressor.

(8) Remove the valve spring retainers and valve

springs.

(9) Remove the valve stem seals from the top of

the valve guides and detach the exhaust valve rotators
and the inlet valve spring seats, from the cylinder
head.

(10) Remove any burrs from the valve stem

grooves to prevent damage to the valve guides when
the valves are removed from the cylinder head.

(11) Remove the valves, keeping them in order

for assembly to their original locations.

NOTE: To keep the valve assemblies in
order have a rack numbered from 1 to 8 and
instill the components in this rack, starting
from the front of the cylinder head.

(12) If the oil pressure relief valve in the cylinder

head is to be renewed, proceed as follows:

(a) Using a drift, remove the welch plug from

the distributor end of the cylinder head.

(b) Remove the recessed screw from the thermo-

stat housing end of the cylinder head.

(c) Using a long brass drift inserted in the oilway

through the tappet bores from the thermostat housing
end. remove the oil pressure relief valve from the
cylinder head. Discard the relief valve.

TO CLEAN AND INSPECT

(1) Clean the valves thoroughly and discard any

burnt, warped or cracked valves.

(2) Have the valves refaced to the recommended

angle on a valve refacing machine. The valve stem tips
are specially hardened and should not be refaced.

Dismantled view of the valve and spring components

.