SUBARU LEGACY 1997 Service Repair Manual

5. Intake Manifold Vacuum
A: MEASUREMENT
1) Warm-up the engine.
2) Disconnect the brake vacuum hose and install the
vacuum gauge to the hose fitting on the manifold.
G2M0099
3) Keep the engine at the idle speed and read the vacuum
gauge indication.
By observing the gauge needle movement, the internal
condition of the engine can be diagnosed as described
below.
Vacuum pressure (at idling, A/C“OFF”):
Less than 60.0 kPa
(450 mmHg, 17.72 inHg)
Diagnosis of engine condition by measurement of manifold vacuum
Vacuum gauge indication Possible engine condition
1. Needle is steady but lower than normal position. This
tendency becomes more evident as engine temperature
rises.Leakage around intake manifold gasket or disconnection or
damaged vacuum hose
2. When engine speed is reduced slowly from higher speed,
needle stops temporarily when it is lowering or becomes
steady above normal position.Back pressure too high, or exhaust system clogged
3. Needle intermittently drops to position lower than normal
position.Leakage around cylinder
4. Needle drops suddenly and intermittently from normal
position.Sticky valves
5. When engine speed is gradually increased, needle begins
to vibrate rapidly at certain speed, and then vibration
increases as engine speed increases.Weak or broken valve springs
6. Needle vibrates above and below normal position in narrow
range.Defective ignition system or throttle chamber idle adjustment
6
2-2
5. Intake Manifold Vacuum

G2M0088
6. Engine Oil Pressure
A: MEASUREMENT
1) Remove generator from bracket.
(1) Disconnect connector and terminal from generator.
G2M0089
(2) Remove V-belt cover.
(3) Loosen lock bolt and slider bolt, and remove V-belt
for generator.
G2M0090
(4) Remove generator lock bolt.
(5) Remove bolt which install generator on bracket.
G2M0091
2) Disconnect connector from oil pressure switch.
3) Remove oil pressure switch from engine cylinder block.
7
2-2
6. Engine Oil Pressure

G2M0093
4) Connect oil pressure gauge hose to cylinder block.
5) Start the engine, and measure oil pressure.
Oil pressure:
98 kPa (1.0 kg/cm
2,14 psi) or more at 800 rpm
294 kPa (3.0 kg/cm2, 43 psi) or more at 5,000 rpm
CAUTION:

If oil pressure is out of specification, check oil
pump, oil filter and lubrication line.
<Ref. to 2-4 [K100].>

If oil pressure warning light is turned ON and oil
pressure is in specification, replace oil pressure
switch.
<Ref. to 2-4 [W3A0].>
NOTE:
The specified data is based on an engine oil temperature
of 80°C (176°F).
6) After measuring oil pressure, install oil pressure switch.
Tightening torque:
25±3 N⋅m (2.5±0.3 kg-m, 18.1±2.2 ft-lb)
7) Install generator and V-belt in the reverse order of
removal, and adjust the V-belt deflection.
8
2-2
6. Engine Oil Pressure

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. <Ref. to 2-2
[07B1].>
10
2-2
7. Valve Clearance

B2M1230A
8) Similar to measurement procedures used for #1
cylinder, measure #2, #3 and #4 cylinder valve clearances.
NOTE:

Be sure to set cylinder pistons to their respective top
dead centers on compression stroke before measuring
valve clearances.

To set #3, #2 and #4 cylinder pistons to their top dead
centers on compression stroke, turn crankshaft pulley
clockwise 90°at a time starting with arrow mark on right-
hand camshaft sprocket facing up.
9) After inspection, install the related parts in the reverse
order of removal.
2. 2500 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 canister.
4) Remove one bolt which secures timing belt cover (RH).
5) Lift-up the vehicle.
6) Remove under cover (RH).
7) Remove canister bracket.
8) Loosen remaining bolts which secure timing belt cover
(RH), then remove belt cover.
9) Lower the vehicle.
B2M1225A
10) Remove rocker cover.

When inspecting #1 and #3 cylinders;
(1) Disconnect connector from mass air flow sensor.
11
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

B2M1233A
B2M1234A
11) Turn crankshaft pulley clockwise until arrow mark on
camshaft sprocket is set to position shown in figure.
12) Measure #1 cylinder intake valve and #3 cylinder
exhaust valve clearances by using thickness gauge.
CAUTION:

Insert the thickness gauge in as horizontal a direc-
tion as possible with respect to the shim.

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)
13) If necessary, adjust the valve clearance. <Ref. to 2-2
[07B2].>
B2M1235A
14) Further turn crankshaft pulley clockwise. Using the
same procedures as in step 12) above, measure valve
clearances.
(1) Set arrow mark on camshaft sprocket to position
shown in figure, and measure #2 cylinder exhaust valve
and #3 cylinder intake valve clearances.
B2M1236A
(2) Set arrow mark on camshaft sprocket to position
shown in figure, and measure #2 cylinder intake valve
and #4 cylinder exhaust valve clearances.
B2M1237A
(3) Set arrow mark on camshaft sprocket to position
shown in figure, and measure #1 cylinder exhaust valve
and #4 cylinder intake valve clearances.
15) After inspection, install the related parts in the reverse
order of removal.
13
2-2
7. Valve Clearance

B2M1228A
B: ADJUSTMENT
1. 2200 cc MODEL
CAUTION:
Adjustment of valve clearance should be performed
while engine is cold.
1) 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.
B2M1238A
2) Adjust the #1 cylinder valve clearance.
(1) Loosen the valve rocker nut and screw.
(2) Place suitable thickness gauge.
(3) While noting valve clearance, tighten valve rocker
adjust screw.
(4) When specified valve clearance is obtained, tighten
valve rocker nut.
Tightening torque:
10±1 N⋅m (1.0±0.1 kg-m, 7.2±0.7 ft-lb)
CAUTION:

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

Adjust 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)
3) Ensure that valve clearances are within specifications.
4) Turn crankshaft two complete rotations until #1 cylinder
piston is again set to top dead center on compression
stroke.
5) Ensure that valve clearances are within specifications.
If necessary, re-adjust valve clearances.
14
2-2
7. Valve Clearance

B2M1230A
6) Similar to adjustment procedures used for #1 cylinder,
adjust #2, #3 and #4 cylinder valve clearances.
NOTE:

Be sure to set cylinder pistons to their respective top
dead centers on compression stroke before adjusting valve
clearances.

To set #3, #2 and #4 cylinder pistons to their top dead
centers on compression stroke, turn crankshaft pulley
clockwise 90°at a time starting with arrow mark on right-
hand camshaft sprocket facing up.
B2M1234A
2. 2500 cc MODEL
CAUTION:
Adjustment of valve clearance should be performed
while engine is cold.
1) Measure all valve clearances. <Ref. to 2-2 [07A2].>
NOTE:
Record each valve clearance after it has been measured.
2) Remove timing belt, camshaft sprockets, and related
parts. <Ref. to 2-3b [W2A0].>
3) Remove camshaft. <Ref. to 2-3b [W3A0].>
B2M1240A
4) Remove shim from valve lifter.
5) Measure thickness of shim with micrometer.
15
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7. Valve Clearance