Nissan PULSAR N13 Series / ASTRA LD Series. Instruction — part 14

Engine

57

(23) Lower the vehicle to the ground and securely

tighten the wheel nuts.

10. PISTONS, CONNECTING RODS AND

CYLINDER BORES

Special Equipment Required:

To Inspect — Micrometer, cylinder measuring

gauge

To Remove Ridge from Bores — Ridge removal tool

To Deglaze Cylinder Bores — Cylinder surfacing

hone

To Install — Piston ring compressor

TO REMOVE

(1) Remove the engine sump and oil pump

pickup pipe as previously described.

(2) Remove the cylinder head as previously

described.

(3) Mark the relationship of the pistons to their

respective cylinders and the bearing caps to their
respective connecting rods by letter stamps or centre
punch marks.

(4) Measure each connecting rod for side clear-

ance on the crankpin. Refer to the illustration. If the
clearance exceeds the Specifications a new connecting
rod will have to be installed on assembly.

(5) With number one cylinder on the bottom of

its stroke, remove the bearing cap bolts and the
bearing cap.

Wipe the bearing shell and the exposed part of the

journal with a piece of clean lint free cloth, insert a
piece of Plastigage across the journal, install the
bearing cap and tighten the bolts to the specified
torque.

Remove the bolts and cap and measure (with the

scale on the packet) the spread width of the Plastigage
to determine the bearing clearance.

Compare the measurement to the Specifications

and if the bearing clearance exceeds the limit, install a
new bearing on assembly.

Repeat the procedure on the remaining cylinders

and note each individual bearing clearance for assem-
bly purposes.

NOTE: Do not rotate the engine while the
Plastigage is in position or false readings
will result.

Dismantled view of the piston and connecting rod

components.

(6) Remove each bearing cap in turn, keeping

them in order, and using a wooden hammer shaft,
push each piston assembly from the cylinder block
and install its respective bearing cap.

NOTE: Before removing the pistons, remove
the ridge from the top of the cylinder bore
using a ridge removal tool.

(7) Remove the piston rings over the top of the

piston and discard the piston rings.

Checking the connecting rod side clearance using feeler

gauges.

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Engine

TO INSPECT PISTONS AND CONNECTING

RODS

(1) Remove all carbon deposits from the bottom

of the ring grooves with a ring groove cleaning tool or
a broken ring. Use caution to avoid scoring the
bottom and sides of the ring groove.

NOTE; An ideal method of removing carbon
deposits from pistons is to immerse the
piston in a tank of chemical cleaner. After
soaking, the carbon can be readily hosed off
with water. This method minimizes the
chance of damage through scraping, particu-
larly with aluminum alloy components.

(2) Inspect the pistons for scuff marks, scoring or

burning.

(3) Inspect the ring grooves of the pistons for

excessive wear. Using a new piston ring, check the
clearances between the side of the ring and the ring
lands of the piston with feeler gauges. Compare the
side clearance with the Specifications.

(4) Inspect each pair of bearing shells for wear

especially on an outer edge. If one or more pairs of
bearing shells are worn on the outer edge it is possible
that the connecting rod is bent.

(5) Before renewing a piston or connecting rod,

inspect the cylinder block to see if it requires reboring
or honing.

If the cylinder block requires reboring, new over-

size pistons will have to be installed.

(6) If a piston or connecting rod is to be

renewed, a special tool will be required to press the
gudgeon pin from the connecting rod. To install the
piston and gudgeon pin to the connecting rod, the
gudgeon pin boss must be accurately heated to 280
degrees C before the gudgeon pin can be inserted in
the little end of the connecting rod.

Replacement connecting rods are supplied only at

their highest production weight and must be matched
to the weight of the remaining connecting rods by
filing the big end boss. For these reasons it is
recommended that the work be entrusted to a repu-
table engine reconditioner who will have the special-
ised equipment and knowledge to carry out this work.

TO INSPECT CYLINDER BLOCK AND BORES

With the pistons removed as previously de-

scribed, carry out the following checks and measuring
procedures:

(1) Check the cylinder bores for cracks, scores or

scuffs.

Check for cylinder bore wear. Difference between A

and B measurement at top of piston travel is out of

round dimension. Difference between A at top and at

bottom of piston travel is cylinder taper.

(2) Using an accurate cylinder gauge, measure

each cylinder bore for wear. Take the measurements,
at the upper and lower sections of the bore in two
directions — along and across the cylinder block.
Refer to the illustration.

(3) If the wear in any cylinder exceeds the

specified limit, rebore and hone all the cylinders to the
nearest oversize for pistons and rings.

(4) With a straight edge and feeler gauge, check

the top face of the cylinder block for distortion, using
the same procedure described for the cylinder head.

STRAIGHT EDGE

Measuring the piston ring side clearance.

Checking the cylinder block face for distortion.

Engine

59

(5) If the engine is completely dismantled, thor-

oughly clean the cylinder block with solvent and
compressed air paying particular attention to the
oilways. Inspect the block for cracks and damage.

TO CHECK PISTON CLEARANCE

(1) Using an accurate cylinder measuring gauge,

measure and note the diameter of each bore as
previously described.

(2) Measure each piston skirt using a microme-

ter as follows:

(a) On 1.6 liter models, measure each piston

skirt at a point 9 mm above the bottom skirt edge and
at right angles to the gudgeon pin axis.

(b) On 1.8 liter models, measure each piston

skirt at a point 6 mm above the bottom skirt edge and
at right angles to the gudgeon pin axis.

(3) The difference between the bore and the

piston measurement is the piston clearance. If the
clearance exceeds the Specifications, renew the pistons
and rebore all the cylinders.

(4) Cylinders that have had new pistons installed

or that have been rebored should have the piston
clearance checked again.

and not engine or transmission oil, mineral spirits or
kerosene.

(2) Honing should be carried out by moving the

hone up and down fast enough to obtain a cross hatch
pattern. When hone marks intersect at 60 degrees, the
pattern is most satisfactory for correct seating of rings.

(3) After honing it is necessary that the block be

cleaned again to remove all traces of abrasives.

NOTE: When deglazing, the cylinder should
be honed only sufficiently to eliminate the
glazed condition. Excessive honing will in-
crease the bore size and alter the piston
clearance.

(4) When honing is complete, ensure that the

cylinder bore, crankcase area and oilways are thor-
oughly cleaned.

(5) After the cylinder block has been cleaned and

dried, wipe the bores with a lint free cloth and smear
them with engine oil to prevent rusting.

NOTE: All abrasives must be removed from
the engine components after honing. A so-
lution of soap and water should be used with
a brush and the components thoroughly
dried. A bore can be considered clean when
it can be wiped clean with a white cloth and
the cloth remains clean. Oil the bores after
cleaning to prevent rusting.

TO FIT NEW PISTON RINGS AND INSTAL
PISTONS

Once the correct piston and the bore relationship

has been determined and the pistons cleaned or
renewed as necessary, proceed as follows:

(1) Place a ring into number one cylinder bore

and using an inverted piston push the ring down 50
mm into the cylinder bore.

(2) Withdraw the piston and measure the gap in

the ring with feeler gauges. Adjust the end gap of the
ring by filing as necessary. See the Specifications for
the ring end gap.

Measuring the piston diameter using a micrometer. On

1.6 liter models, dimension A = 9 mm. On 1.8 liter

models, dimension A - 6 mm.

TO INSPECT AND DEGLAZE CYLINDER
BORES

Cylinder bores that are fit for further service with

the original pistons, but require re-ringing, should be
deglazed with a hone. Before honing the cylinder
bores with crankshaft installed, place plenty of clean
rag over the crankshaft to keep the abrasive materials
from entering the crankcase area.

(1) Deglaze the cylinder walls using a cylinder

surfacing hone equipped with suitable stones. Inspect
the cylinder walls after each 20 strokes. Use honing oil

Checking the piston ring end gap.

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Engine

NOTE: Should the ring end gap be greater
than the specified gap, another ring set
should be obtained and the ring end gaps
checked and compared with the Specifica-
tions.

(3) Treat each ring and cylinder bore individu-

ally and ensure that the rings are assembled to the
respective piston for the cylinder bore in which they
were installed to check the end gap.

(4) Assemble each oil control ring to its respec-

tive piston bottom groove as follows:

(a) Install the oil ring expander to the

piston
groove, ensuring that the ends of the expander are
bulled together and not overlapped.

(b) Position one end of the lower side rail in the

groove and peel the ring over the piston and into the
groove.

(c) Similarly install the upper side rail.

(5) Install the lower compression ring into

the
lower piston groove.

NOTE: The compression rings should be
installed with the manufacturers mark fac-
ing the top of the piston. To minimize the
possibility of ring breakage the rings can be
immersed in hot water prior to installation.

(6) Install the upper compression ring into

the
upper piston groove.

(7) Space the compression ring gaps 120 degrees

apart, and ensure that the oil ring gaps and the join in
the oil ring expander are not aligned.

(8) With the rings correctly installed and

gapped, remove the bearing cap from the connecting
rod.

(9) Liberally lubricate the piston assembly and

install the piston ring compressor to number one
piston.

NOTE: When installing the pistons to the

cylinder ensure that the front marking on
the piston is towards the front of the engine.

(10) Turn the crankshaft until number one crank-

pin is at the bottom of its stroke.

(11) Install number one piston and connecting

rod
assembly into its bore. Push the assembly down the
bore until the connecting rod can be aligned with
number one crankpin.

NOTE: The bearing shells should be lubri-
cated with engine oil before installation.

(12) Install the connecting rod cap and tighten

the
retaining bolts to the specified torque.

NOTE: If new bearing shells were installed,
check the bearing clearance with Plastigage
as previously described.

(13) With the bearing clearance as specified, in-

stal the remaining pistons in the same manner.

(14) Ensure that the crankshaft turns without

binding.

(15) With all connecting rod bolts tightened to

the specified torque, install the associated
components
by referring to the relevant headings in this section.

11. CRANKSHAFT AND MAIN BEARINGS

Special Equipment Required:

To Inspect — Micrometer, Vee blocks, dial gauge

TO REMOVE

(1) With the engine assembly removed from the

vehicle and the transaxle separated from the engine,
refer to the appropriate headings or sections and
remove the following components: sump, oil pump
pickup pipe, oil pump, and flywheel or drive plate.

(2) Remove the crankshaft rear oil seal from the

Using a ring compressor to install the piston.

Checking the crankshaft end float using feeler gauges

.