1999 SUBARU LEGACY timing belt

2. Engine Noise
If noise still exists, conduct diagnostics procedures
in accordance with the following table.CAUTION:
Do not disconnect spark plug cord while
engine is running.
Type of sound Condition Possible cause
Regular clicking soundSound increases as engine
speed increases.Valve mechanism is defective.
IIncorrect valve clearance
IWorn camshaft
IBroken valve spring
Heavy and dull clankOil pressure is low.IWorn crankshaft main bearing
IWorn connecting rod bearing (big end)
Oil pressure is normal.ILoose flywheel mounting bolts
IDamaged engine mounting
High-pitched clank
(Spark knock)Sound is noticeable when
accelerating with an overload.IIgnition timing advanced
IAccumulation of carbon inside combustion chamber
IWrong spark plug
IImproper gasoline
Clank when engine speed is
medium (1,000 to 2,000 rpm).Sound is reduced when fuel
injector connector of noisy cyl-
inder is disconnected.
(NOTE*)IWorn crankshaft main bearing
IWorn 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 cyl-
inder is disconnected.
(NOTE*)IWorn cylinder liner and piston ring
IBroken or stuck piston ring
IWorn piston pin and hole at piston end of connecting rod
Sound is not reduced if each
fuel injector connector is dis-
connected in turn.
(NOTE*)IUnusually worn valve lifter
IWorn camshaft journal bore in crankcase
Squeaky sound ÐIInsufficient generator lubrication
Rubbing sound ÐIDefective generator brush and rotor contact
Gear scream when starting
engineÐIDefective ignition starter switch
IWorn gear and starter pinion
Sound like polishing glass with
a dry clothÐILoose drive belt
IDefective engine coolant pump shaft
Hissing sound ÐILoss of compression
IAir leakage in air intake system, hoses, connections or
manifolds
Timing belt noise ÐILoose timing belt
IBelt contacting case/adjacent part
Valve tappet noise ÐIIncorrect valve clearance
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. [T6A0].>
76
2-3b[K200]DIAGNOSTICS
2. Engine Noise

11) Remove crankshaft pulley by using ST.
ST 49997700 CRANKSHAFT PULLEY
WRENCH
S2M0114
12) Remove water pump.
S2M0022
13) Remove timing belt guide. (MT vehicles only)
S2M0115
14) Remove crankshaft sprocket.
S2M0116
15) Remove bolts which install oil pump onto cyl-
inder block.
S2M0117
16) Remove oil pump by using flat bladed screw-
driver.
CAUTION:
Be careful not to scratch mating surfaces of
cylinder block and oil pump.
S2M0722A
7
[W1A0]2-4SERVICE PROCEDURE
1. Oil Pump

5) Disconnect radiator outlet hose (A) and heater
by-pass hose (B) from water pump.
H2M2515A
6) Disconnect connectors from radiator main fan
(A) and sub fan (B) motors.
B2M2035A
7) Lower the vehicles.
8) Remove radiator main fan [W6A0].> and sub fan motor assembly [W7A0].>.
B2M2036
9) Remove V-belts.

B2M2308
10) Remove timing belt.

B2M2037
11) Remove automatic belt tension adjuster.
H2M2375
12) Remove belt idler No. 2.
H2M2518
13) Remove camshaft position sensor.

B2M2038
9
[W2A1]2-5SERVICE PROCEDURE
2. Water Pump

4) Drain engine coolant completely.

B2M0015A
5) Disconnect connectors from radiator main fan
(A) and sub fan (B) motors.
B2M2035A
6) Loosen bolts which hold lower side of radiator
main fan and sub fan shrouds.
B2M2041
7) Disconnect radiator outlet hose (A) and heater
by-pass hose (B) from water pump.
H2M2515A
8) Lower the vehicle.
9) Remove radiator main fan [W6A0].> and sub fan assemblies [W7A0].>.
B2M2036
10) Remove V-belts.

B2M2308
11) Remove timing belt.

S2M0017
12) Remove automatic belt tension adjuster.
H2M2403
11
[W2A2]2-5SERVICE PROCEDURE
2. Water Pump

1. Engine Cooling System Trouble in General
TroubleCorrective action
Over-heatinga. Insufficient engine coolantReplenish engine coolant, inspect for leakage, and
repair.
b. Loose timing belt Repair or replace timing belt tensioner.
c. Oil on drive belt Replace.
d. Malfunction of thermostat Replace.
e. Malfunction of water pump Replace.
f. Clogged engine coolant passage Clean.
g. Improper ignition timingInspect and repair ignition control system.
On-Board Diagnostics II System
h. Clogged or leaking radiator Clean or repair, or replace.
i. Improper engine oil in engine coolant Replace engine coolant.
j. Air/fuel mixture ratio too leanInspect and repair fuel injection system.
On-Board Diagnostics II System
k. Excessive back pressure in exhaust system Clean or replace.
l. Insufficient clearance between piston and cylinder Adjust or replace.
m. Slipping clutch Repair or replace.
n. Dragging brake Adjust.
o. Improper transmission oil Replace.
p. Defective thermostat Replace.
q. Malfunction of electric fanInspect radiator fan relay, engine coolant temperature
sensor or radiator motor and replace there.
Over-coolinga. Atmospheric temperature extremely low Partly cover radiator front area.
b. Defective thermostat Replace.
Engine coolant
leaks.a. Loosened or damaged connecting units on
hosesRepair or replace.
b. Leakage from water pump Replace.
c. Leakage from water pipe Repair or replace.
d. Leakage around cylinder head gasket Retighten cylinder head bolts or replace gasket.
e. Damaged or cracked cylinder head and crank-
caseRepair or replace.
f. Damaged or cracked thermostat case Repair or replace.
g. Leakage from radiator Repair or replace.
Noisea. Defective drive belt Replace.
b. Defective radiator fan Replace.
c. Defective water pump bearing Replace water pump.
d. Defective water pump mechanical seal Replace water pump.
26
2-5[K100]DIAGNOSTICS
1. Engine Cooling System Trouble in General