4A–FE engine is an in–line, 4–cylinder, 1.6 liter DOHC 16–valve engine. Manual - part 26

INSPECTION OF PISTON AND CONNECTING
ROD ASSEMBLIES

1. CLEAN PISTON

(a) Using a gasket scraper, remove the carbon from the

piston top.

3. DISCONNECT CONNECTING ROD FROM PISTON

Using SST, press out the piston pin from the piston.
Remove the connecting rod.
SST 09221–25024 (09221–00020, 09221–00030,

09221–00050,09221–00130,09221–00140)

HINT:

•

The piston and pin are a matched set.

•

Arrange the pistons, pins, rings, connecting
rods and bearings in correct order.

(b) Remove the two side rails and oil ring expander

by hand.

HINT: Arrange the rings in correct order only.

(b) Using a groove cleaning tool or broken ring,

clean the piston ring grooves.

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ENGINE MECHANICAL

Cylinder Block (4A–FE)

EM–202

2. INSPECT PISTON
A. Inspect piston oil clearance

HINT: There are three sizes of the standard piston di-
ameter, marked ”1 ”, ”2” and ”3” accordingly. The mark
is stamped on the piston top.
(a) Using a micrometer, measure the piston diameter at

right angles to the piston pin center line, 22.5 mm
(0.886 in.) from the piston head.

Piston diameter:

STD Mark ”1 ” 80–930 – 80. 940 mm

(3.1862 – 3.1866 in.)

Mark ”2”  80.940 – 80. 950 mm

(3.1866 – 3.1870 in.)

Mark ”3”  80.950 – 80.960 mm

(3.1870 – 3.1874 in.)

O/S 

0.50 81.430 – 81.460 mm

(3.2059 – 3.2071 in.)

(b) Measure the cylinder bore diameter in the thrust

directions. (See step 4 on page 

EM–201

 )

(c) Subtract the piston diameter measurement from the

cylinder bore diameter measurement.

Standard oil clearance: 0.060 – 0.080 mm

(0.0024 – 0.0031 in.)

Maximum oil clearance: 0.10 mm (0.0039 in.)
If the oil clearance is greater than maximum, replace all
the four pistons and rebore all the four cylinders. If nec-
essary, replace the cylinder block.
HINT (Use new cylinder block) : Use a piston with the
same number mark as the cylinder bore diameter
marked on the cylinder block.

(c) Using solvent and a brush, thoroughly clean the

piston.

NOTICE: Do not use a wire brush.

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ENGINE MECHANICAL

Cylinder Block (4A–FE)

EM–203

(c) Using a feeler gauge, measure the end gap.
Standard end gap:

No.1 

0.250 – 0.450 mm

(0–0098 – 0.0177 in.)

No.2 

0.150 – 0.400 mm

(0.0059 – 0.0157 in.)

Oil (Side rail) 

0.100 – 0.700 mm

(0–0039 – 0.0276 in.)

Maximum end gap:

No.1 

1.05 mm (0.0413 in.)

No.2 

1.00 mm (0.0394 in.)

Oil (Side rail) 

1.30 mm (0.0512 in.)

If the end gap is greater than maximum, replace the
piston ring. If the end gap is greater than maximum,
even with a new piston ring, rebore all the four cylinders
or replace the cylinder block.

3. INSPECT CONNECTING ROD

Using rod aligner and feeler gauge, check the connect-
ing rod alignment.

•

Check for bending.

Maximum bending:

0.05 mm (0.0020 in.) per 100 mm (3.94 in.)

If bend is greater than maximum, replace the connecting
rod and connecting rod cap as a set.

•

Check for twist.

Maximum twist:

0.05 mm (0.0020 in.) per 100 mm (3.94 in.)

If twist is greater than maximum, replace the connecting
rod and connecting rod cap as a set.

B. Inspect piston ring groove clearance

Using a feeler gauge, measure the clearance between
new piston ring and the wall of the piston ring groove.
Ring groove clearance:
No .10.040 – 0.081 mm (0.0016 – 0.0032 in.)
No . 20.030 – 0.070 mm ( 0.0012 – 0.0028 in.)
If the clearance is greater than maximum, replace the
piston.

C. Inspect piston ring end gap

(a) Insert the piston ring into the cylinder bore.
(b) Using a piston, push the piston ring a little beyond

the bottom of the ring travel, 87 mm (3.43 in.) from
the top of the cylinder block.

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ENGINE MECHANICAL

Cylinder Block (4A–FE)

EM–204

BORING OF CYLINDERS

HINT:

•

Bore all the four cylinders for the oversized piston
outside diameter.

•

Replace all the piston rings with ones to match the
oversized pistons.

1. KEEP OVERSIZED PISTONS
Oversized piston diameter:

O/S 0.50 

81.430 – 81.460 mm
(3.2059 – 3.2071 in.)

2. CALCULATE AMOUNT TO BORE CYLINDERS

(a) Using a micrometer, measure the piston diameter at

right angles to the piston pin center line, 22.5 mm
(0.886 in.) from the piston head.

(b) Calculate the amount each cylinder is to be rebored

as follows:
Size to be rebored = P + C – H

P = Piston diameter
C = Piston clearance

0.060 – 0.080 mm (0.0024 – 0.0031 in.)

H = Allowance for honing

0.02 mm (0.0008 in.) or less

3. BORE AND HONE CYLINDERS TO CALCULATED

DIMENSIONS
Maximum honing: 0.02 mm (0.0008 in.)
NOTICE: Excess honing will destroy the finished
roundness.

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ENGINE MECHANICAL

Cylinder Block (4A–FE)

EM–205

2. INSPECT MAIN JOURNALS AND CRANK PINS

(a) Using a micrometer, measure the diameter of each

main journal and crank pin.

Main journal diameter:

STD 

47–982 – 48.000 mm
(1.8891 –1.8898 in.)

U /S 0.25 

47.745 – 47.755 mm
(1.8797 – 1.8881 in.)

Crank pin diameter:

STD 

39–985 – 40.000 mm
(1. 5742 – 1.5748 in.)

U/S 0.25 

39.745 – 39.755 mm
(1.5648 – 1.5652 in.)

If the diameter is not as specified, check the oil clearance
(See pages 

EM–194

 to 198). If necessary, grind or r

place the crankshaft.
(b) Check each main journal and crank pin for taper and

out–of–round as shown.

Maximum taper and out–of–round: 0.02 mm

(0.0008 in.)

If the taper and out–of–round is greater than maximum,
replace the crankshaft.

3. IF NECESSARY, GRIND AND HONE MAIN JOURNALS

AND/OR CRANK PINS
Grind and hone the main journals and/or crank pins to
the finished undersized diameter.
(See procedure step 2 above).
Install new main journal and/or crank pin undersized
bearings.

INSPECTION AND REPAIR OF CRANKSHAFT

1. INSPECT CRANKSHAFT FOR RUNOUT

(a) Place the crankshaft on V–blocks.
(b) Using a dial indicator, measure the circle runout at

the center journal.

Maximum circle runout: 0.06 mm (0.0024 in.)
If the circle runout is greater than maximum, replace the
crankshaft.

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ENGINE MECHANICAL

Cylinder Block (4A–FE)

EM–206

(b) Using SST and a hammer, tap in a new oil seal

until its surface is flush with the oil pump case
edge.

SST 09309–37010
(c) Apply MP grease to the oil seal lip.

B. If oil pump is installed to the cylinder block:

(a) Using a knife, cut off the oil seal lip.
(b) Using a screwdriver, pry out the oil seal.
NOTICE: Be careful not to damage the crankshaft.

Tape the screwdriver tip.

(c) Apply MP grease to a new oil seal lip.
(d) Using SST and a hammer, tap in the oil seal until

its surface is flush with the oil pump case edge.

SST 09309–37010

REPLACEMENT OF CRANKSHAFT
OIL SEALS

HINT: There are two methods (A and B) to replace the
oil seal which are as follows:

1. REPLACE CRANKSHAFT FRONT OIL SEAL
A. If oil pump is removed from cylinder block:

(a) Using a screwdriver, pry out the oil seal.

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ENGINE MECHANICAL

Cylinder Block (4A–FE)

EM–207

B. If rear oil seal retainer is installed to cylinder block:

(a) Using a knife, cut off the oil seal lip.
(b) Using a screwdriver, pry out the oil seal.
NOTICE: Be careful not to damage the crankshaft.

Tape the screwdriver tip.

(b) Using SST and a hammer, tap in a new oil seal

until its surface is flush with the rear oil seal
edge.

SST 09223–41020
(c) Apply MP grease to the oil seal lip.

(c) Apply MP grease to a new oil seal lip.
(d) Using SST and a hammer, tap in the oil seal until

its surface is flush with the rear oil seal retainer
edge.

SST 09223–41020

2. REPLACE CRANKSHAFT REAR OIL SEAL
A. If rear oil seal retainer is removed from cylinder block:

(a) Using screwdriver and hammer, tap out the oil seal.

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ENGINE MECHANICAL

Cylinder Block (4A–FE)

EM–208

ASSEMBLY OF PISTON AND
CONNECTING ROD ASSEMBLIES

1. ASSEMBLE PISTON AND CONNECTING ROD

(a) Coat the piston pin and pin holes of the piston with

engine oil.

(b) Align the front marks of the piston and connecting

rod.

(c) Position the piston rings so that the ring ends are

as shown.

NOTICE: Do not align the ring ends.

(b) Using a piston ring expander, install the two compres-

sion rings with the code mark facing upward
(No.2 compression ring only).

Code mark (No.2 compression ring only): R or T

2. INSTALL PISTON RINGS

(a) Install the oil ring expander and two side rails by

hand.

(c) Using SST, press in the piston pin.

SST 09221–25024 (09221–00020, 09221–00030,

09221–00050,09221–00130,09221–00140)

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ENGINE MECHANICAL

Cylinder Block (4A–FE)

EM–209