spark plug SUBARU LEGACY 1997 Service Repair Manual

1. Foreword
This chapter describes major inspection and service pro-
cedures for the engine mounted on the body. For proce-
dures not found in this chapter, refer to the service proce-
dure section in the applicable chapter.
2. Ignition Timing
A: MEASUREMENT
1. 2200 cc MODEL
1) Warm-up the engine.
G2M0094
2) To check the ignition timing, connect a timing light to #1
cylinder spark plug cord, and illuminate the timing mark
with the timing light.
3) Start the engine at idle speed and check the ignition
timing.
If the timing is not correct, check the ignition control sys-
tem.
Ignition timing [BTDC/rpm]:
14°±8°/700 (MT)
20°±8°/700 (AT)
2. 2500 cc MODEL
CAUTION:
After warming-up, engine becomes very hot. Be care-
ful not to burn yourself during measurement.
1) Warm-up the engine.
B2M0750A
2) To check the ignition timing, connect a timing light to #1
cylinder spark plug cord, and illuminate the timing mark
with the timing light.
3) Start the engine at idle speed and check the ignition
timing.
If the timing is not correct, check the ignition control sys-
tem.
Ignition timing [BTDC/rpm]:
15°±8°/700
2
2-2
1. Foreword - 2. Ignition Timing

1. Foreword
This chapter describes major inspection and service pro-
cedures for the engine mounted on the body. For proce-
dures not found in this chapter, refer to the service proce-
dure section in the applicable chapter.
2. Ignition Timing
A: MEASUREMENT
1. 2200 cc MODEL
1) Warm-up the engine.
G2M0094
2) To check the ignition timing, connect a timing light to #1
cylinder spark plug cord, and illuminate the timing mark
with the timing light.
3) Start the engine at idle speed and check the ignition
timing.
If the timing is not correct, check the ignition control sys-
tem.
Ignition timing [BTDC/rpm]:
14°±8°/700 (MT)
20°±8°/700 (AT)
2. 2500 cc MODEL
CAUTION:
After warming-up, engine becomes very hot. Be care-
ful not to burn yourself during measurement.
1) Warm-up the engine.
B2M0750A
2) To check the ignition timing, connect a timing light to #1
cylinder spark plug cord, and illuminate the timing mark
with the timing light.
3) Start the engine at idle speed and check the ignition
timing.
If the timing is not correct, check the ignition control sys-
tem.
Ignition timing [BTDC/rpm]:
15°±8°/700
2
2-2
1. Foreword - 2. Ignition Timing

3. Engine Idle Speed
A: MEASUREMENT
1) Before checking idle speed, check the following:
(1) Ensure that air cleaner element is free from
clogging, ignition timing is correct, spark plugs are in
good condition, and that hoses are connected properly.
(2) Ensure that malfunction indicator light (CHECK
ENGINE light) does not illuminate.
2) Warm-up the engine.
G2M0096
3) Connect Subaru Select Monitor or the OBD-II general
scan tool to data link connector.
CAUTION:
When connecting Subaru Select Monitor, turn ignition
switch to OFF.
4) Start the engine and measure engine speed.
NOTE:
Engine speed is indicated on Subaru Select Monitor by
selecting “MODE F04”.
G2M0097
NOTE:

When using the OBD-II general scan tool, carefully read
its operation manual.

When Subaru Select Monitor is not used, attach the
pickup sensor on tachometer (Secondary pickup type) to
#1 cylinder spark plug cord.

This ignition system provides simultaneous ignition for
#1 and #2 plugs. It must be noted that some tachometers
may register twice that of actual engine speed.
5) Check idle speed when unloaded. (With headlights,
heater fan, rear defroster, radiator fan, air conditioning, etc.
OFF)
Idle speed (No load and gears in neutral (MT) or N or
P (AT) position):
700±100 rpm
6) Check idle speed when loaded. (Turn air conditioning
switch to “ON” and operate compressor for at least one
minute before measurement.)
Idle speed [A/C“ON”, no load and gears in neutral
(MT) or N or P (AT) position]:
850±50 rpm
CAUTION:
Never rotate idle adjusting screw. If idle speed is out
of specifications, refer to General On-board Diagnosis
Table under “2-7 On-Board Diagnostics II System”.
3
2-2
3. Engine Idle Speed

4. Engine Compression
A: MEASUREMENT
1. 2200 cc MODEL
1) After warming-up the engine, turn ignition switch to
OFF.
2) Make sure that the battery is fully charged.
3) Remove all the spark plugs.
4) Disconnect connectors from fuel injectors.
5) Fully open throttle valve.
6) Check the starter motor for satisfactory performance
and operation.
G2M0098
7) Hold the compression gauge tight against the spark
plug hole.
CAUTION:
When using a screw-in type compression gauge, the
screw (put into cylinder head spark plug hole) should
be less than 18 mm (0.71 in) long.
8) Crank the engine by means of the starter motor, and
read the maximum value on the gauge when the pointer is
steady.
9) Perform at least two measurements per cylinder, and
make sure that the values are correct.
Compression (200—300 rpm and fully open throttle):
Standard
1,079—1,275 kPa
(11.0—13.0 kg/cm
2, 156—185 psi)
Limit
883 kPa (9.0 kg/cm
2, 128 psi)
Difference between cylinders
196 kPa (2.0 kg/cm
2, 28 psi)
2. 2500 cc MODEL
CAUTION:
After warming-up, engine becomes very hot. Be care-
ful not to burn yourself during measurement.
1) After warming-up the engine, turn ignition switch to
OFF.
2) Make sure that the battery is fully charged.
3) Remove all the spark plugs. [W3E0].>
4) Disconnect connectors from fuel injectors.
4
2-2
4. Engine Compression

5) Fully open throttle valve.
6) Check the starter motor for satisfactory performance
and operation.
B2M0752A
7) Hold the compression gauge tight against the spark
plug hole.
CAUTION:
When using a screw-in type compression gauge, the
screw (put into cylinder head spark plug hole) should
be less than 18 mm (0.71 in) long.
8) Crank the engine by means of the starter motor, and
read the maximum value on the gauge when the pointer is
steady.
9) Perform at least two measurements per cylinder, and
make sure that the values are correct.
Compression (350 rpm and fully open throttle):
Standard
1,216 kPa
(12.4 kg/cm
2, 176 psi)
Limit
941 kPa (9.6 kg/cm
2, 137 psi)
Difference between cylinders
49 kPa (0.5 kg/cm
2, 7 psi), or less
5
2-2
4. Engine Compression

7. Valve Clearance
A: INSPECTION
1. 2200 cc MODEL
CAUTION:
Inspection and adjustment of valve clearance should
be performed while engine is cold.
1) Set the vehicle onto the lift.
2) Disconnect battery ground cable.
3) Remove timing belt cover (RH).
B2M1225A
4) Remove rocker cover.

When inspecting #1 and #3 cylinders;
(1) Disconnect connector from mass air flow sensor.
B2M1226A
(2) Loosen clamp which connects air intake duct to air
intake chamber.
(3) Remove the two clips from air cleaner upper cover.
CAUTION:
Before installing air cleaner upper cover, align hole(s)
with protruding portions of air cleaner lower case, then
secure upper cover.
(4) Disconnect blow-by hose from air intake duct.
B2M1227
(5) Remove air intake duct and air cleaner upper cover
as a unit.
(6) Remove air cleaner element.
(7) Disconnect spark plug cords from spark plugs (#1
and #3 cylinders).
(8) Remove under cover (RH).
(9) Place suitable container under the vehicle.
(10) Disconnect PCV hose from rocker cover (RH).
(11) Remove bolts, then remove rocker cover (RH).
9
2-2
7. Valve Clearance

When inspecting #2 and #4 cylinders;
(1) Disconnect battery cables, and then remove bat-
tery and battery carrier.
(2) Disconnect washer motor connectors.
(3) Disconnect rear window glass washer hose from
washer motor, then plug connection with a suitable cap.
(4) Remove the two bolts which holds washer tank,
then secure the tank away from working area.
(5) Disconnect spark plug cords from spark plugs (#2
and #4 cylinders).
(6) Remove under cover (LH).
(7) Place suitable container under the vehicle.
(8) Disconnect PCV hose from rocker cover (LH).
(9) Remove bolts, then remove rocker cover (LH).
B2M1228A
5) Set #1 cylinder piston to top dead center of compres-
sion stroke by rotating crankshaft pulley clockwise.
NOTE:
When arrow mark on camshaft sprocket (RH) comes
exactly to the top, #1 cylinder piston is brought to the top
dead center of compression stroke.
B2M1229A
6) Measure #1 cylinder valve clearance by using thickness
gauge.
CAUTION:

Insert the thickness gauge in as horizontal a direc-
tion as possible with respect to the valve stem end
face.

Measure exhaust valve clearances while lifting-up
the vehicle.
Valve clearance:
Intake: 0.20±0.02 mm (0.0079±0.0008 in)
Exhaust: 0.25±0.02 mm (0.0098±0.0008 in)
7) If necessary, adjust the valve clearance. [07B1].>
10
2-2
7. Valve Clearance

B2M1226A
(2) Loosen clamp which connects air intake duct to air
intake chamber.
(3) Remove the two clips from air cleaner upper cover.
CAUTION:
Before installing air cleaner upper cover, align hole(s)
with protruding portions of air cleaner lower case, then
secure upper cover.
(4) Disconnect blow-by hose from air intake duct.
B2M1227
(5) Remove air intake duct and air cleaner upper cover
as a unit.
(6) Remove air cleaner element.
B2M1232A
(7) Remove air cleaner lower case.
(8) Disconnect spark plug cords from spark plugs (#1
and #3 cylinders).
(9) Place suitable container under the vehicle.
(10) Disconnect PCV hose from rocker cover (RH).
(11) Remove bolts, then remove rocker cover (RH).

When inspecting # 2 and #4 cylinders;
(1) Disconnect battery cables, and then remove bat-
tery and battery carrier.
(2) Disconnect washer motor connectors.
(3) Disconnect washer hoses from washer motors,
then plug connections with suitable caps.
(4) Remove washer tank.
(5) Disconnect spark plug cords from spark plugs (#2
and #4 cylinders).
(6) Remove under cover (LH).
(7) Place suitable container under the vehicle.
(8) Disconnect PCV hose from rocker cover (LH).
(9) Remove bolts, then remove rocker cover (LH).
12
2-2
7. Valve Clearance

G2M0106
1. General Precautions
1) Before disassembling engine, place it on ST3.
ST1 498457000 ENGINE STAND ADAPTER RH
ST2 498457100 ENGINE STAND ADAPTER LH
ST3 499817000 ENGINE STAND
2) All parts should be thoroughly cleaned, paying special
attention to the engine oil passages, pistons and bearings.
3) Rotating parts and sliding parts such as piston, bearing
and gear should be coated with oil prior to assembly.
4) Be careful not to let oil, grease or coolant contact the
timing belt, clutch disc and flywheel.
5) All removed parts, if to be reused, should be reinstalled
in the original positions and directions.
6) Gaskets and lock washers must be replaced with new
ones. Liquid gasket should be used where specified to
prevent leakage.
7) Bolts, nuts and washers should be replaced with new
ones as required.
8) Even if necessary inspections have been made in
advance, proceed with assembly work while making
rechecks.
2. Hydraulic Lash Adjuster
A: INSPECTION
1) Disconnect blow-by hose from rocker cover.
2) Remove spark plug cap.
B2M0413A
3) Remove left and right rocker covers.
CAUTION:
Before removing left rocker cover, disconnect battery
cables and generator cable.
11
2-3SERVICE PROCEDURE
1. General Precautions - 2. Hydraulic Lash Adjuster

G2M0106
1. General Precautions
1) Before disassembling engine, place it on ST3.
ST1 498457000 ENGINE STAND ADAPTER RH
ST2 498457100 ENGINE STAND ADAPTER LH
ST3 499817000 ENGINE STAND
2) All parts should be thoroughly cleaned, paying special
attention to the engine oil passages, pistons and bearings.
3) Rotating parts and sliding parts such as piston, bearing
and gear should be coated with oil prior to assembly.
4) Be careful not to let oil, grease or coolant contact the
timing belt, clutch disc and flywheel.
5) All removed parts, if to be reused, should be reinstalled
in the original positions and directions.
6) Gaskets and lock washers must be replaced with new
ones. Liquid gasket should be used where specified to
prevent leakage.
7) Bolts, nuts and washers should be replaced with new
ones as required.
8) Even if necessary inspections have been made in
advance, proceed with assembly work while making
rechecks.
2. Hydraulic Lash Adjuster
A: INSPECTION
1) Disconnect blow-by hose from rocker cover.
2) Remove spark plug cap.
B2M0413A
3) Remove left and right rocker covers.
CAUTION:
Before removing left rocker cover, disconnect battery
cables and generator cable.
11
2-3SERVICE PROCEDURE
1. General Precautions - 2. Hydraulic Lash Adjuster