2008 Lexus GS350 Engine cooling

402
4-3. Do-it-yourself maintenance
GS_G_U
June 19, 2008 12:54 pm
CAUTION
The engine compartment contains many mechanisms and fluids that may move sud-
denly, become hot, or become electrically energized. To avoid death or serious injury,
observe the following precautions.
■When working on the engine compartment
●Keep hands, clothing, and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, radiator, exhaust manifold, etc. right after driv-
ing as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper or rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel or the 12 volt battery.
Fuel and 12 volt battery fumes are flammable.
●Be extremely cautious when working on the 12 volt battery. It contains poisonous
and corrosive sulfuric acid.
■When working near the electric cooling fan or radiator grille
Be sure the “ENGINE START STOP” switch is OFF.
With the “ENGINE START STOP” switch in IGNITION ON mode, the electric
cooling fan may automatically start to run if the air conditioning is on and/or the
coolant temperature is high. (→P. 4 1 5 )
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting
in the eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear due to
dirt in the air. Also a backfire could cause a fire in the engine compartment.
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406
4-3. Do-it-yourself maintenance
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Engine compartment
GS460
Engine oil level dipstick(→P. 4 0 9 )
Engine oil filler cap (→P. 4 1 0 )
Brake fluid reservoir (→P. 4 1 6 )
Fuse box ( →P. 4 4 2 )
Washer fluid tank (→P. 4 2 0 )Engine coolant reservoir
(→P. 4 1 4 )
Electric cooling fans
Condenser ( →P. 415)
Radiator ( →P. 415)
Fuse box ( →P. 4 4 2 )
12 volt battery ( →P. 417)
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4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_G_U
June 19, 2008 12:54 pm
GS350
Engine oil level dipstick(→P. 4 0 9 )
Engine oil filler cap (→P. 4 1 0 )
Brake fluid reservoir (→P. 4 1 6 )
Fuse box ( →P. 4 4 2 )
Washer fluid tank (→P. 4 2 0 )Engine coolant reservoir
(→P. 4 1 4 )
Electric cooling fans
Condenser ( →P. 415)
Radiator ( →P. 415)
Fuse box ( →P. 4 4 2 )
12 volt battery ( →P. 417)
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414
4-3. Do-it-yourself maintenance
GS_G_U
June 19, 2008 12:54 pm
CoolantThe coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the engine is cold. Reservoir cap
“FULL”
“LOW”
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line.
■If the coolant level drops within a short time after replenishing
Visually check the radiator, hoses, reservoir cap, radiator cap, drain cock and water
pump.
If you cannot find a leak, have your Lexus dealer pressure test the cap and check for
leaks in the cooling system.
■Coolant selection
Only use “Toyota Super Long Life Coolant” or similar high quality ethylene glycol
based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life
hybrid organic acid technology.U.S.A.: “Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deionized water. (Enabled: -31 °F [-35 °C])
Canada: “Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deionized water. (Enabled: -44 °F [-42 °C])
For more details about coolant, contact your Lexus dealer.
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4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_G_U
June 19, 2008 12:54 pm
Radiator and condenserCheck the radiator and condenser and clear any foreign objects.
If either of the above parts are extremely dirty or you are not sure of their
condition, have your vehicle checked by your Lexus dealer.
CAUTION
■When the engine is hot
Do not remove the radiator and reservoir cap.
The cooling system may be under pressure and may spray hot coolant if the cap is
removed, causing burns or other injuries.
NOTICE
■When adding the coolant
Coolant is neither plain water not straight antifreeze. The correct mixture of water
and antifreeze must be used to provide proper lubrication, corrosion protection
and cooling. Be sure to read the antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to prevent it from damaging to parts or paint.
CAUTION
■When the engine is hot
Do not touch the radiator or condenser, as they may be hot and you may be burned.
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4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_G_U
June 19, 2008 12:54 pm
FuseAmpereCircuit
18VGRS40VGRS
19MAIN30H-LP R LWR and H-LP L LWR
20STARTER30Starting system
21LH J/B-B30FL DOOR, RL DOOR and RAD
NO.3
22VVT40Electronic engine control system
23EPS80EPS
24ALT180
RH J/B-AM, LH J/B-AM, E/G-AM,
RR JB, HEATER, DEFOG, FAN1,
FAN2, ABS2, ABS MOTOR,
ABS MAIN1, and ABS MAIN2
25RH J/B-AM80
AM1, OBD, STOP SW, TI&TE,
PWR OUTLET, FR P/SEAT RH,
STR LOCK, ECU-IG RH, RH-IG,
ACC, CIG, SECURITY,
FR S/HTR RH and AIR SUS
26FA N 380Electric cooling fans
27LH J/B-AM80
S/ROOF, P/SEAT, TV, FL S-HTR,
ECU-IG L, WIP, H-LP LVL, LH-IG,
FUEL OPN, A/C, PANEL, LH-B and
TRK OPN
28ABS230ABS
29DEFFOG50Rear window defogger, noise filter
30CDS40CDS
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5
When trouble arises
533
5-2. Steps to take in an emergency
GS_G_U
June 19, 2008 12:54 pm
If your vehicle overheats
If your engine overheats:
Stop the vehicle in a safe place and turn off the air conditioning
system.
Check to see if steam is coming out from under the hood.
If you see steam: Stop the engine and carefully lift the hood.
If you do not see steam: Leave the engine running and carefully lift the hood.
Remove the engine compartment cover. ( →P. 4 0 8 )
Check to see if the cooling fan is operating.
If the fan is operating: Wait until the engine coolant temperature gauge begins to
fall and then stop the engine.
If the fan is not operating: Stop the engine immediately and call your local Lexus
dealer.
After the engine has cooled
down sufficiently, check the
coolant level and inspect the
radiator core (radiator) for any
leaks.STEP1
STEP2
STEP3
STEP4
STEP5
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546
6-1. Specifications
GS_G_U
June 19, 2008 12:54 pm
Cooling system
Ignition system
CapacityGS46011.7 qt. (11.0 L, 9.7 Imp.qt.)
GS3509.6 qt. (9.1 L, 8.0 Imp.qt.)
Coolant type
Use either of the following:
• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based non-sili-cate, non-amine, non-nitrite, and non-borate cool-
ant with long-life hybrid organic acid technology
Do not use plain water alone.
Spark plug
Make DENSOFK20HBR11
Gap0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust gap when tuning engine.
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