fuel SUBARU LEGACY 1995 Service Repair Manual

4. Engine Compression
A: 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.
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)
5
2-2
4. Engine Compression

3. RELATED PARTS
1) Install valve rocker assembly.

B2M0418B
Tightening torque: N⋅m (kg-m, ft-lb)
T1: 5±1 (0.5±0.1, 3.6±0.7)
T2: 12±1 (1.2±0.1, 8.7±0.7)
2) Install timing belt, camshaft sprockets and related parts.

6. Cylinder Head
A: REMOVAL
1. INTAKE MANIFOLD
1) Release fuel pressure.
2) Drain engine coolant.
3) Remove intake manifold.
4) Remove engine coolant pipe.
38
2-3SERVICE PROCEDURE
5. Camshaft - 6. Cylinder Head

3. RELATED PARTS
1) Install valve rocker assembly.

B2M0418B
Tightening torque: N⋅m (kg-m, ft-lb)
T1: 5±1 (0.5±0.1, 3.6±0.7)
T2: 12±1 (1.2±0.1, 8.7±0.7)
2) Install timing belt, camshaft sprockets and related parts.

6. Cylinder Head
A: REMOVAL
1. INTAKE MANIFOLD
1) Release fuel pressure.
2) Drain engine coolant.
3) Remove intake manifold.
4) Remove engine coolant pipe.
38
2-3SERVICE PROCEDURE
5. Camshaft - 6. Cylinder Head

1. Engine Trouble in General
Numbers shown in the chart refer to the possibility of reason for the
trouble in order (“Very often”to“Rarely”)
1—Very often
2—Sometimes
3—Rarely
TROUBLE
Engine will not start.
Rough idle and engine stall
Low output, hesitation and poor acceleration
Surging
Engine does not return to idle.
Dieseling (Run-on)
After burning in exhaust system
Knocking
Excessive engine oil consumption
Excessive fuel consumption Starter does not turn.
Initial combustion does not occur.
Initial combustion occurs.
Engine stalls after initial combustion.
POSSIBLE CAUSE
STARTER
2Defective battery-to-starter harness
3Defective starter switch
3Defective inhibitor switch
23Defective starter
BATTERY
1Poor terminal connection
1Run-down battery
2Defective charging system
1111111111 1Fuel injection system Diagnostics II System.>
75
2-3DIAGNOSTICS
1. Engine Trouble in General

TROUBLE
Engine will not start.
Rough idle and engine stall
Low output, hesitation and poor acceleration
Surging
Engine does not return to idle.
Dieseling (Run-on)
After burning in exhaust system
Knocking
Excessive engine oil consumption
Excessive fuel consumption Starter does not turn.
Initial combustion does not occur.
Initial combustion occurs.
Engine stalls after initial combustion.
INTAKE SYSTEM
2111 3Loosened or cracked intake air pipe
3111 3 1Loosened or cracked blow-by hose
31211 2Loosened or cracked vacuum hose
22222Defective intake manifold gasket
22222Defective throttle body gasket
322 2 2Defective PCV valve
222 323Loosened oil filler cap
3312 1Dirty air cleaner element
FUEL LINE
13 322Defective fuel pump and relay
33322Clogged fuel line
222233Lack of or insufficient fuel
BELT
222Defective
222322 22 2Defective timing
FRICTION
3Seizure of crankshaft and connecting rod bearing
3Seized camshaft
3Seized or stuck piston and cylinder
COMPRESSION
333222 23 2Defective hydraulic lash adjuster
333223 3 3Loosened spark plugs or defective gasket
333223 3 3Loosened cylinder head bolts or defective gasket
333223 2 2Improper valve seating
333333 3 13Defective valve stem
222223 3 3Worn or broken valve spring
333233 3 12Worn or stuck piston rings, cylinder and piston
222111 12 2Incorrect valve timing
222222Improper engine oil (low viscosity)
76
2-3DIAGNOSTICS
1. Engine Trouble in General

TROUBLE
Engine will not start.
Rough idle and engine stall
Low output, hesitation and poor acceleration
Surging
Engine does not return to idle.
Dieseling (Run-on)
After burning in exhaust system
Knocking
Excessive engine oil consumption
Excessive fuel consumption Starter does not turn.
Initial combustion does not occur.
Initial combustion occurs.
Engine stalls after initial combustion.
LUBRICATION SYSTEM
22 3 3Incorrect oil pressure
2Loosened oil pump attaching bolts and defective
gasket
2Defective oil filter seal
2Defective crankshaft oil seal
32Defective rocker cover gasket
2Loosened oil drain plug or defective gasket
2Loosened oil pan fitting bolts or defective oil pan
COOLING SYSTEM
33221Overheating
333Over cooling
OTHERS
113 3Malfunction of Evaporative Emission Control
System
21Stuck or damaged throttle valve
322 2Accelerator cable out of adjustment
77
2-3DIAGNOSTICS
1. Engine Trouble in General

2. Engine Noise
Valve lash adjusters may make clicking noise once engine
starts. It is normal if clicking noise ceases after a few min-
utes.
If clicking noise continues after a few minutes, check
engine oil level and add oil if necessary.
Then, do as follows to cease clicking noise.
1) Warm-up engine for five minutes.
2) Turn ignition switch OFF.
3) Connect test mode connector.
4) Start the engine and run it at approximately 2,000 rpm
for twenty minutes.
5) Turn ignition switch OFF.
6) Disconnect test mode connector.
7) Start the engine and check that clicking noise is ceased.
If noise still exists, conduct troubleshooting procedures in
accordance with the following table.
CAUTION:
Do not disconnect spark plug cord while engine is run-
ning.
Type of sound Condition Possible cause
Regular clicking soundSound increases as engine
speed increases.Valve mechanism is defective.
Broken lash adjuster
Worn valve rocker
Worn camshaft
Broken valve spring
Worn valve lifter hole
Heavy and dull clankOil pressure is low.Worn crankshaft main bearing
Worn connecting rod bearing (big end)
Oil pressure is normal.Loose flywheel mounting bolts
Damaged engine mounting
High-pitched clank
(Spark knock)Sound is noticeable when
accelerating with an overload.Ignition timing advanced
Accumulation of carbon inside combustion chamber
Wrong spark plug
Improper gasoline
Clank when engine speed is
medium (1,000 to 2,000 rpm).Sound is reduced when fuel
injector connector of noisy
cylinder is disconnected.
(NOTE*)Worn crankshaft main bearing
Worn bearing at crankshaft end of connecting rod
Knocking sound when engine
is operating under idling speed
and engine is warm.Sound is reduced when fuel
injector connector of noisy
cylinder is disconnected.
(NOTE*)Worn cylinder liner and piston ring
Broken or stuck piston ring
Worn piston pin and hole at piston end of connecting rod
Sound is not reduced if each
fuel injector connector is
disconnected in turn. (NOTE*)Unusually worn valve lifter
Worn cam gear
Worn camshaft journal bore in crankcase
Squeaky sound—Insufficient generator lubrication
Rubbing sound—Defective generator brush and rotor contact
Gear scream when starting
engine—Defective ignition starter switch
Worn gear and starter pinion
Sound like polishing glass with
a dry cloth—Loose drive belt
Defective engine coolant pump shaft
78
2-3DIAGNOSTICS
2. Engine Noise

Type of sound Condition Possible cause
Hissing sound—Loss of compression
Air leakage in air intake system, hoses, connections or
manifolds
Timing belt noise—Loose timing belt
Belt contacting case/adjacent part
NOTE*:
When disconnecting fuel injector connector, Malfunction Indicator Light (CHECK ENGINE light) illuminates and trouble code is stored in
ECM memory.
Therefore, carry out the CLEAR MEMORY MODE and INSPECTION MODE after connecting fuel injector connector. (Ref. to 2-7 On-Board
Diagnostics II System.)
79
2-3DIAGNOSTICS
2. Engine Noise

B2M0323
5) Remove radiator fan motor assembly.
6) Remove fan motor from shroud.
B: INSTALLATION
Installation is in the reverse order of removal procedures.
Do the following:
1) Before installing radiator fan motor, apply a coat of seal-
ant to threads and tighten nuts.
2) Make sure radiator fan does not come into contact with
shroud when installed.
3) After installation, make sure there is no unusual noise
or vibration when fan is rotated.
G6M0095
7. Engine Coolant Pipe
A: REMOVAL
1) Release fuel pressure.

2) Disconnect ground cable from the battery.
B2M0015A
3) Drain engine coolant completely.

B2M0160
4) Remove intake manifold.

16
2-5SERVICE PROCEDURE
6. Radiator Fan and Fan Motor - 7. Engine Coolant Pipe

B2M0323
5) Remove radiator fan motor assembly.
6) Remove fan motor from shroud.
B: INSTALLATION
Installation is in the reverse order of removal procedures.
Do the following:
1) Before installing radiator fan motor, apply a coat of seal-
ant to threads and tighten nuts.
2) Make sure radiator fan does not come into contact with
shroud when installed.
3) After installation, make sure there is no unusual noise
or vibration when fan is rotated.
G6M0095
7. Engine Coolant Pipe
A: REMOVAL
1) Release fuel pressure.

2) Disconnect ground cable from the battery.
B2M0015A
3) Drain engine coolant completely.

B2M0160
4) Remove intake manifold.

16
2-5SERVICE PROCEDURE
6. Radiator Fan and Fan Motor - 7. Engine Coolant Pipe