1995 SUBARU LEGACY Knock

G2M0198
4) Manually push valve rocker (at lash adjuster location) to
check that there is no air in it.
NOTE:
When air is in lash adjuster, valve rocker moves when
pushed with fingers.
G2M0199
5) If air is in lash adjuster, remove valve rocker assembly
from engine and bleed air completely.
B2M0382A
B: AIR BLEEDING
1) Remove valve rocker assembly.
(1) Remove bolts

1through
4in numerical
sequence.
CAUTION:
Leave two or three threads of bolt

1engaged to retain
valve rocker assembly.
(2) Equally loosen bolts

5through
8all the way,
being careful that knock pin is not gouged.
2) Manually remove lash adjusters where air is trapped.
CAUTION:
If lash adjuster is difficult to remove manually, use pli-
ers. Be careful not to scratch lash adjuster.
12
2-3SERVICE PROCEDURE
2. Hydraulic Lash Adjuster

6) Fill rocker arm’s oil reservoir with engine oil and install
lash adjuster.
CAUTION:
Do not rotate lash adjuster during installation.
Be careful not to scratch the oil seal.
B2M0414
CAUTION:
When removing valve rocker assembly, keep the
assembly soaked in engine oil, or position it with air
bleeding orifice on rocker arm facing upward as
shown. This prevents oil leakage from and air entering
into the hydraulic lash adjuster. Failure to do so may
cause air to enter the hydraulic lash adjuster, causing
loss in performance.
B2M0382B
7) Temporarily and equally tighten bolts
1through
4.Do
not allow knock pin to catch valve rocker assembly.
8) Tighten bolts

5through
8to specified torque.
9) Tighten bolts

1through
4to specified torque.
Tightening torque:
12±1 N⋅m (1.2±0.1 kg-m, 8.7±0.7 ft-lb)
10) Install rocker covers.
Tightening torque:
5±1 N⋅m (0.5±0.1 kg-m, 3.6±0.7 ft-lb)
11) Connect harness connectors, hoses, etc. to their posi-
tions.
14
2-3SERVICE PROCEDURE
2. Hydraulic Lash Adjuster

4. Valve Rocker Assembly
A: REMOVAL
B2M0418A
B2M0382A
1) Disconnect PCV hose and remove rocker cover.
2) Removal of valve rocker assembly
(1) Remove bolts

1through
4in numerical sequence.
CAUTION:
Leave two or three threads of bolt

1engaged to retain
valve rocker assembly.
(2) Equally loosen bolts

5through
8all the way, being
careful that knock pin is not gouged.
B2M0414
(3) Remove valve rocker assembly.
CAUTION:
Locate valve rocker assembly with air vent (on rocker
arm) facing upward or dip it in engine oil after removal.
27
2-3SERVICE PROCEDURE
4. Valve Rocker Assembly

E: INSTALLATION
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)
B2M0382B
1) Installation of valve rocker assembly
(1) Temporarily tighten bolts

1through
4equally as
shown in Figure.
CAUTION:
Do not allow valve rocker assembly to gouge knock
pins.
(2) Tighten bolts

5through
8to specified torque.
(3) Tighten bolts

1through
4to specified torque.
2) Install rocker cover and connect PCV hose.
32
2-3SERVICE PROCEDURE
4. Valve Rocker Assembly

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