cooling NISSAN PATROL 1998 Y61 / 5.G Engine Mechanical Workshop Manual

NVH Troubleshooting Chart Ð Engine Noise
Use the chart below to help you ®nd the cause of the problem.
1. Locate the area where noise occurs.
2. Con®rm the type of noise.
3. Specify the operating condition of engine.
4. Check speci®ed noise source.
If necessary, repair or replace these parts.
Location of
noiseType of
noiseOperating condition of engine
Source of
noiseCheck itemReference
page Before
warm-upAfter
warm-upWhen
startingWhen
idlingWhen
racingWhile
driving
To p o f
engine
Rocker
cover
Cylinder
headTicking or
clickingCAÐABÐTappet
noiseValve clearance EM-41
Rattle C A Ð A B CCamshaft
bearing
noiseCamshaft journal clearance
Camshaft runoutEM-37
Crankshaft
pulley
Cylinder
block (Side
of engine)
Oil panSlap or
knockÐAÐB BÐPiston pin
noisePiston and piston pin clear-
ance
Connecting rod bushing
clearanceEM-47, 53
Slap or rap A Ð Ð B B APiston slap
noisePiston-to-bore clearance
Piston ring side clearance
Piston ring end gap
Connecting rod bend and
torsionEM-48, 49
Knock A B C B B BConnecting
rod bearing
noiseConnecting rod bushing
clearance (Small end)
Connecting rod bearing
clearance (Big end)EM-52, 53
Knock A B Ð A B CMain bear-
ing noiseMain bearing oil clearance
Crankshaft runoutEM-51
Timing belt
coverWhine or
hissingCAÐAAÐTiming belt
noise (too
tight)
Loose timing belt
Belt contacting caseEM-18
Clatter A B Ð C A ÐTiming belt
noise (too
loose)
Front of
engineSqueaking
or ®zzingABÐBÐCOther drive
belts
(Sticking or
slipping)Drive belts de¯ection
*1
CreakingABABABOther drive
belts (Slip-
ping)Idler pulley bearing operation
Squall
CreakABÐBABWater pump
noiseWater pump operation *2
A: Closely related B: Related C: Sometimes related Ð: Not related
*1: MA section (``Checking Drive Belts'', ``ENGINE MAINTENANCE'')
*2: LC section (``Water Pump Inspection'', ``ENGINE COOLING SYSTEM'')
NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
EM-8

CAUTION:
+Do not bend or twist timing belt.
+After removing timing belt, do not turn crankshaft and
camshaft separately because valves will strike piston
heads.
+Make sure that timing belt, camshaft sprocket, crankshaft
sprocket, idler pulley, injection pump pulley and belt ten-
sioner are clean and free from oil and water.
+Align white lines on timing belt with punch mark on cam-
shaft sprocket, crankshaft sprocket and injection pump
pulley.
+Installation should be carried out when engine is cold.
Removal
1. Remove radiator shroud.
2. Remove the following belts.
+Power steering drive belt
+A/C compressor drive belt
+Alternator drive belt
3. Remove cooling fan coupling and water pump pulley.
SMA767BA
TIMING BELT
EM-16

3. Install tensioner spring and tighten belt tensioner lock nut.
:32-40Nzm
(3.3 - 4.1 kg-m, 24 - 30 ft-lb)
4. Install front cover.
5. Install crankshaft pulley.
6. Install water pump pulley and cooling fan coupling.
7. Apply liquid gasket to the connecting surface and install the
starter motor.
Use Genuine Liquid Gasket or equivalent.
8. Install drive belts and check drive belt de¯ections by pushing
midway between pulleys.
Refer to MA section (``Checking Drive Belts'').
SMA770B
SMA015C
TIMING BELT
Installation (Cont'd)
EM-20