2004 YAMAHA YZ85 radiator cap

3 - 8
INSP
ADJRADIATOR CAP OPENING PRESSURE INSPECTION/
COOLING SYSTEM INSPECTION
RADIATOR CAP OPENING PRESSURE
INSPECTION
1. Attach:

Radiator cap tester 1

Radiator cap tester adapter 2
NOTE:
Apply water on the radiator cap seal.
3Radiator cap
2. Apply the specified pressure.
3. Inspect:

Pressure
Impossible to maintain the specified pres-
sure for 10 seconds → Replace.
Radiator cap tester:
YU-24460-01/90890-01325
Radiator cap tester adapter:
YU-33984/90890-01352
Radiator cap opening pressure:
95 ~ 125 kPa (0.95 ~ 1.25 kg/cm2,
13.5 ~ 17.8 psi)
5PA30060
COOLING SYSTEM INSPECTION
1. Inspect:

Coolant level
2. Attach:

Radiator cap tester 1

Radiator cap tester adapter 2
3. Apply the specified pressure.
Radiator cap tester:
YU-24460-01/90890-01325
Radiator cap tester adapter:
YU-33984/90890-01352
Standard pressure:
180 kPa (1.8 kg/cm2, 25.6 psi)
5PA30070

4 - 4
ENGRADIATOR
EC456000
HANDLING NOTE
WARNING
Do not remove the radiator cap when the
engine and radiator are hot. Scalding hot
fluid and steam may be blown out under
pressure, which could cause serious
injury.
When the engine has cooled, open the radi-
ator cap by the following procedure:
Place a thick rag, like a towel, over the radi-
ator cap, slowly rotate the cap counter-
clockwise to the detent. This procedure
allows any residual pressure to escape.
When the hissing sound has stopped,
press down on the cap while turning coun-
terclockwise and remove it.
EC454000
INSPECTION
Radiator
1. Inspect:

Radiator core 1
Obstruction → Blow out with compressed
air through rear of the radiator.
Bent fin → Repair or replace.
5PA40040
EC455000
ASSEMBLY AND INSTALLATION
Radiator
1. Install:

Radiator breather hose 1
To radiator 2.
5PA40050
2. Install:

Radiator 1

Bolt (radiator) 2
5PA40060

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ENG
4. Install:

O-ring 1
NOTE:
Apply the lithium soap base grease on the O-
rings.
5PA40690
5. Install:

Cylinder head 1

Copper washer 2

Nut (cylinder head) 3
NOTE:
Tighten the nuts (cylinder head) in stage, using
a crisscross pattern.
5PA40700
T R..30 Nm (3.0 m · kg, 22 ft · lb)
6. Install:

Spark plug 1

Spark plug cap 2

Radiator hose 1 3

Radiator hose 2 4
5PA40710
T R..20 Nm (2.0 m · kg, 14 ft · lb)
CYLINDER HEAD, CYLINDER AND PISTON

4 - 49
ENG
EC4M0000
ENGINE REMOVAL
5PA41490
Extent of removal Order Part name Q’ty Remarks
ENGINE REMOVAL
Preparation for removal Hold the machine by placing the
suitable stand under the frame.
WARNING
Support the machine securely so there is no
danger of it falling over.
Drain the coolant. Refer to “COOLANT REPLACEMENT”
section in the CHAPTER 3.
Seat and fuel tank Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section.
Carburetor Refer to “CARBURETOR AND REED
VALVE” section.
Exhaust pipe and silencer Refer to “EXHAUST PIPE AND
SILENCER” section.
Clutch cable Disconnect at engine side.
Radiator hose 1 Disconnect at cylinder head side.
Radiator hose 2 Disconnect at water pump side.
Spark plug cap
Disconnect the CDI magneto
lead.
ENGINE REMOVAL