Yamaha YZ 2019 Series, Owner'S Service Manual

Page: 96 / 398

ENGINE
3-8
5. Install:
• Copper washer
•
Coolant drain bolt
6. Pour coolant.
WARNING
EWA13040
• If coolant splashes in your eyes, thorough-
ly wash them with water and consult a doc-
tor.
• If coolant splashes on your clothes, quickly
wash it away with water and then with soap
and water.
• If coolant is swallowed, induce vomiting
and get immediate medical attention.
NOTICE
ECA13481
• Adding water instead of coolant lowers the
antifreeze content of the coolant. If water is
used instead of coolant, check, and if nec-
essary, correct the antifreeze concentra-
tion of the coolant.
• Use only distilled water. However, if dis-
tilled water is not available, soft water may
be used.
• If coolant comes into contact with painted
surfaces, immediately wash them with wa-
ter.
• Do not mix different types of antifreeze.
7. Install:
• Radiator cap
8. Start the engine, warm this up for 3 minutes,
stop it, and then wait for it to cool down.
9. Check:
• Coolant level
Refer to “CHECKING THE COOLANT LEV-
EL” on page 3-7.
EAM30213
CHECKING THE RADIATOR CAP
1. Check:
•
Seal (radiator cap) “1”
•
Valve and valve seat “2”
Crack/damage

Replace.
Exist fur deposits

Clean or replace.
EAM30214
CHECKING THE RADIATOR CAP VALVE
OPENING PRESSURE
1. Check:
•
Radiator cap valve opening pressure
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Install the radiator cap tester adapter “2” and
the radiator cap tester “3” to the radiator cap
“1”, and activate the tester to check whether
it can stay for 5 to 10 seconds within standard
pressure values.
TIP
Before attaching the cap to the tester, apply wa-
ter to its sealing surface.
No stay

Replace.
Coolant drain bolt
10 N·m (1.0 kgf·m, 7.4 lb·ft)
Recommended coolant
High quality ethylene glycol
anti-freeze containing anti-cor-
rosion for aluminum engine
Radiator (including all routes)
1.00 L (1.06 US qt, 0.88 Imp.qt)
Coolant mixing ratio
1:1 (Coolant:Water)
New
T
R
.
.
Radiator cap valve opening pres-
sure
107.9–137.3 kPa (1.08–1.37
kgf/cm², 15.6–19.9 psi)
Radiator cap tester
90890-01325
Mityvac cooling system tester kit
YU-24460-A
Radiator cap tester adapter
90890-01352
Pressure tester adapter
YU-33984