1987 NISSAN PULSAR fold seats

Engine 39
Oil pump cover plate screws............................ 6 Nm
Oil pump mounting bolts.................................. 6 Nm
Oil pump pickup bolts
(coat with Loctite 242)..................................... 8 Nm
Sump bolts (coat with Loctite 242) .................. 5 Nm
Sump drain plug .............................................. 35 Nm
*Use new bolts
Head bolts maximum torque 135 Nm

1. ENGINE MECHANICAL TROUBLE
SHOOTING

ENGINE MISSES AT IDLING SPEED
NOTE: For other causes of engine misfire,
refer to the Fuel and Engine Management
section.

(1) Blown head gasket: Check the cylinder com-
pressions and renew the he ad gasket as necessary.
(2) Burnt valves or seats in the cylinder head:
Check the cylinder compressions and overhaul the
cylinder head as necessary. (3) Broken or worn piston rings: Check the
cylinder compressions and renew the piston rings as
necessary.
(4) Weak or broken valve springs: Remove the
camshaft housing top cover and check the condition
of the valve springs. (5) Air leak at the inlet manifold gasket; Check
for air leaks by applying oil around the manifold
joints. Renew the gasket if an air leak is evident.
NOTE: Use a compre ssion gauge and check
the compression pressure in each cylinder as
described in the Engine Tune-up section. If
a low pressure reading is indicated in one or
more cylinders, remove the cylinder head for
gasket and valve inspection. Should the


gasket and valves prove satisfactory, inspect
the cylinder bores, pistons and rings.

Check for air leaks at the inlet manifold
by applying engine oil around the manifold
joints. If the oil can be seen or heard sucking
into the manifold or excessive smoke begins
to issue from the exhaust system, there is an
air leak at the inlet manifold.

NOISY VALVE OPERATION
(1) Faulty hydraulic tappets: Renew the faulty
tappet assemblies. (2) Weak or broken valve springs: Remove the
camshaft housing top cover and check the condition
of the valve springs. (3) Worn valve guides: Overhaul the cylinder
head as described in this section. (4) Worn rocker gear: Remove (he rocker gear
and check the components for wear.

Camshaft lobe wear is also a cause of noisy valve
operation.
BIG END BEARING NOISE
(1) Inadequate oil supply: Check the oil level in
the sump and the condition of the oil pump and relief
valve. Renew the oil filter.

(2) Excessive bearing clearance: Renew the bear-
ing shells, check and regrind the big end journals if
oval or tapered. (3) Thin oil or oil diluted by petrol or water:
Change to the correct oil grade. Check and rectify the
cause of the oil dilution. Ch eck that the engine is not
operating in overheat conditions.
(4) Low oil pressure: Check the engine oil level.
Check the pressure relief valve and spring and the oil
filter bypass valve. (5) Misaligned big end bearings: Align the con-
necting rods and renew the big end bearing shells.
NOTE: Big end bearing noise is indicated
by a metallic knock wh ich is usually loudest
at approximately 60 km/h with the throttle
Air leaks at the inlet manifold can be located by
applying engine oil around the suspect joints.

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 or iginal locations.
(5) Slide each hydraulic tappet from its bore in
the cylinder head, also keeping them in order for
assembly to their or iginal locations.
(6) Before removing the valves the deposits in

Installed view of the cylinder head oil pressure relief
valve.
the combustion chambers s hould 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.

Engine 53


Method of checking cylinder head for distortion.
(3) Carefully clean the deposits from the inlet
and exhaust ports, the auxiliary passages, the valve
guides and the manifolds, taking care not to damage
any mating surfaces. (4) Clean the cylinder head mounting faces,
wash the cylinder head in solvent and dry with
compressed air. Blow through all the oil holes with
compressed air to ensure that they are not blocked. (5) Check the cylinder head for distortion diag-
onally and lengthwise using a straight edge and feeler
gauges. Refer to Specifications for the distortion and
machining limits. (6) Check the cylinder head face and combus-
tion chambers for cracks, burn marks and corrosion. (7) Check the valve stem to guide clearance. If
the clearance is in excess of the Specifications, the
valve guide must be reamed and the appropriate
oversize valve installed. (8) Inspect the valve seats for pitting or burning
and if necessary, recut the seats with a valve seat
cutter to the recommended angle. When the seats are
correctly finished, the seat widths should conform to
the Specifications. (9) Lap the valves to the valve seats with a fine
lapping compound. Apply a smear of Prussian blue to
the valves or their respective seats to ensure that true
and concentric seating has been gained.

(10) Install each valve in its respective port
and
check the valve stem height above the cylinder head.
Refer to the illustration. The extended height must
not exceed 18.4 mm. If the height exceeds the
Specifications, the valve or the cylinder head must be
renewed. Do not remove any material from the valve
stem tip.
(11) Check the valve spring tensions and compare
with the Specifications.
Check that the springs are not bent or distorted.

If a spring tester is not available, check the springs
by comparison with new springs. This can be done
using a surface plate and stra ight edge for checking the
free length and using a new spring and a used spring
loaded in a vice end on end, with a plate in between.
Measure from the plate to the vice jaw adjacent to
both the new and used springs. A used spring is
serviceable if it does not show collapse in excess of
five percent when subjected to this comparison test.

(12) Check the exhaust valve rotators for wear
and ensure that the rotators turn freely. (13) Clean the cylinder block face of all carbon
and rust deposits and ensure that all old gaskets are
removed. Do not allow the waste deposits to enter the
oil or water galleries. Clean all waste materials from the cylinder bores.

TO ASSEMBLE
Assembly is a reversal of the dismantling proce-
dure with attention to the following points:

(1) Lubricate all component wear surfaces with
engine oil before assembly to ensure adequate lubri-
cation when starting. (2) If the oil pressure relief valve was removed
from the cylinder head, proceed as follows:
(a) Using a brass tube inserted in the welch plug
hole at the distributor end of the cylinder head, tap
the relief valve into position. (b) Install the welch plug and the recessed screw
in their respective positions, after coating the plug and
the screw with Loctite 242 or equivalent.
(3) Install the inlet valve spring seats and
the
exhaust valve rotators over the valve guides before
installing the valve stem seals onto the valve guides.
(4) Install the valve stem seals, ensuring that
the
rib of the moulding on the inside of the seal is
correctly positioned in the groove of the valve guide
and that the spring clip retainer is correctly posi-
tioned.
NOTE: The valve stem seals can be posi-
tioned correctly and without damage using
an upturned valve spring retainer.

(5) Install the valves to their original location in
the cylinder head. Use care when installing the valves
to prevent damage to the seals.
(6) Install the valve springs, retainers and
collets.
Ensure that the valve retain ing collets are fully seated
Dimension A is the correct position to measure the
valve stem installed height. Dimension A = 18.4 mm.