Honda Crf250l Service Manual

							8-6
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LUBRICATION SYSTEMASSEMBLY
INSTALLATION
Install the dowel pins [1].
Apply engine oil to a new O-ring [2].
Install the O-ring to the oil pump assembly [3].
Install the oil pump assembly  while aligning its slit with
cam chain guide hook and its hole with the pressure
relief valve.
Install and tighten the oil pump mounting bolts [1].
If the oil pump was disasse mbled, tighten the oil pump
assembly bolt [2].
OIL PUMP BODY
INNER ROTOR
OIL PUMP SHAFT
OUTER ROTOR
OIL PUMP COVER
OIL PUMP DRIVEN GEAR
LOCK PIN
OIL PUMP ASSEMBLY BOLT
WASHER
DOWEL PINS
OIL PUMP MOUNTING BOLTS
O-RING
[3]
[2]
[1]
AlignAlign
[1]
[2] 
						

							8-7
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LUBRICATION SYSTEM
Apply engine oil to the oil pump driven gear [1] teeth.
Install the oil pump driven gear while aligning the flats of
the oil pump driven gear and oil pump shaft.
Install the right crankcase cover (page 12-8).
PRESSURE RELIEF VALVE
REMOVAL/INSTALLATION
Remove the oil pump (page 8-4).
Remove the oil pressure relief valve [1] and O-rings [2].
Apply engine oil to new O-rings.
Install the O-rings to the oil pressure relief valve
grooves.
Install the oil pressure relief valve into the right
crankcase with the piston side facing outside.
Install the oil pump (page 8-6).
PRESSURE RELIEF VALVE 
INSPECTION
Check the operation of the pressure relief valve by
pushing on the piston [1].
Disassemble the pressure relief valve by removing the
snap ring [2].
Remove the washer [1], spring [2] and piston [3].
Check the piston for wear, sticking or damage.
Check the spring for fatigue or damage.
Assemble the pressure relief valve in the reverse order
of disassembly.
 • Install the snap ring with the chamfered edges facingthe thrust load side.
 • Make sure the snap ring is seated in the groove.
[1]
Align
[1]
[2]
[2][1]
[1][2][3] 
						

							MEMO
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							9-1
9
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9. COOLING SYSTEM
SERVICE INFORMATION ·····························9-2
TROUBLESHOOTING···································9-2
SYSTEM FLOW PATTERN ···························9-3
SYSTEM TESTING ········································9-4
COOLANT REPLACEMENT ·························9-5
THERMOSTAT ··············································9-5RADIATOR/COOLING FAN ··················\
········ 9-6
WATER PUMP ·············································· 9-8
RADIATOR RESERVE TANK ··················\
··· 9-12
FAN CONTROL RELAY ····························· 9-12
WATER PIPE ·············································· 9-13 
						

							9-2
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COOLING SYSTEM
COOLING SYSTEMSERVICE INFORMATION
GENERAL
Using coolant with silicate inhibitors may cause premature wear of water pump seals or blockage of radiator passages. Using tap
water may cause engine damage.
 • Add cooling system at the reserve ta nk. Do not remove the radiator cap except to refill or drain the system.
 • All cooling system services can be do ne with the engine installed in the frame.
 • Avoid spilling coolant on painted surfaces.
 • After servicing the system, check for  leaks with a cooling system tester.
TROUBLESHOOTING
Engine temperature too high
 • Faulty indicator or ECT sensor
 • Thermostat stuck closed
 • Faulty radiator cap
 • Insufficient coolant
 • Passage blocked in radiator, hoses or water jacket
 • Air in system
 • Faulty cooling fan motor
 • Faulty fan control relay
 • Faulty water pump
Engine temperature too low
 • Thermostat stuck open
 • Faulty fan control relay
Coolant leak
 • Faulty water pump mechanical seal
 • Deteriorated O-ring
 • Faulty radiator cap
 • Damaged or deteriorated cylinder head gasket
 • Loose hose connection or clamp
 • Damaged or deteriorated hoses
 • Damaged radiator
Removing the radiator cap while the engine is hot can  allow the coolant to spray out, seriously scalding you.
Always let the engine and radiator cool down before removing the radiator cap. 
						

							9-3
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COOLING SYSTEM
SYSTEM FLOW PATTERN
RADIATOR
SIPHON HOSE
THERMOSTAT
WATER PUMP
RESERVE TANK
WATER HOSE
WATER HOSE
WATER PIPE 
						

							9-4
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COOLING SYSTEM
SYSTEM TESTING
RADIATOR CAP/SYSTEM PRESSURE 
INSPECTION
Loosen the cap screw [1] and  remove the radiator cap
[2].
Wet the sealing surfaces of  the radiator cap [1], then
install the cap onto the tester [2].
Pressurize the cap using the tester. Replace the
radiator cap if it does not hold pressure, or if relief
pressure is too high or too low. It must hold the
specified pressure for at least 6 seconds.
Pressurize the radiator, engine and hoses using the
tester, and check for leaks.
Excessive pressure can  damage the cooling system
components. Do not exceed 122.6 kPa (1.25 kgf/cm2,
17.8 psi).
Repair or replace components  if the system will not hold
the specified pressure for at least 6 seconds.
Remove the tester.
Install the radiator cap and tighten the screw.
[1]
[2]
RADIATOR CAP RELIEF PRESSURE:
93.2 – 122.6 kPa 
(0.95 – 1.25 kgf/cm
2, 13.5 – 17.8 psi)
[1]
[2] 
						

							9-5
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COOLING SYSTEM
COOLANT REPLACEMENT
REPLACEMENT/AIR BLEEDING
Remove the radiator cap (page 9-4).
Remove the drain bolt [1] and sealing washer [2] on the
water pump cover and drain the coolant from the
system.
Install and tighten the drain bolt with a new sealing
washer.
Fill the system with the recommended coolant through
the filler opening.
Bleed air from the system as follows:
1. Shift the transmission into neutral.Start the engine and let it idle for 2 – 3 minutes.
2. Snap the throttle 3 – 4 times to bleed air from the system.
3. Stop the engine and add the coolant.
4. Install the radiator cap  and tighten the cap screw.
Remove the reserve tank cap [1] and fill the reserve
tank to the UPPER level line [2].
Install the reserve tank cap.
THERMOSTAT
REMOVAL/INSTALLATION
Drain the coolant (page 9-5).
Remove the bolts [1] and thermostat cover [2].
When filling the
system or reserve
tank with a coolant
(checking coolant
level), support the motorcycle on a
level surface.
RECOMMENDED ANTIFREEZE:High quality ethylene glyc ol antifreeze containing
silicate-free corro sion inhibitors
STANDARD COOLANT  CONCENTRATION:
1:1 (mixture with distilled water)
[1]
[2]
[2]
[1]
[2]
[1] 
						

							9-6
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COOLING SYSTEM
Remove the thermostat [1] from the cylinder head.
Installation is in the reverse order of removal.
 • Install the thermostat with the bleed hole [2] facingup.
 • When installing the thermostat, align the tab of the seal ring [3] with the groove of the thermostat cover.
Fill and bleed the cooling system (page 9-5).
INSPECTION
Visually inspect the thermostat [1] for damage.
Check the seal ring [2] for damage and replace if
necessary.
Wear insulated gloves and
adequate eye
protection. Keep flammable
materials away
from the electric
heating element. Do not let the
thermostat or
thermometer touch the pan, or you will
get false reading.Heat the water with an electric heating element to
operating temperature for 5 minutes.
Suspend the thermostat [1] in heated water to check its
operation.
Replace the thermostat if the valve open at a
temperatures other than those specified.
RADIATOR/COOLING FAN
REMOVAL/INSTALLATION
Drain the coolant (page 9-5).
Remove the left fuel tank shroud (page 2-4).
Release the spark plug wire [1] and radiator siphon
hose [2] from the guides [3].
Disconnect the fan motor 2P (Black) connector [4].
[2]
[3][1]
Align
[2]
[1]
THERMOSTAT BEGIN TO OPEN: 81 – 84°C (178 – 183°F)
VALVE LIFT: 4.5 mm (0.18 in) minimum at 95°C (203°F)
[1]
[4]
[3]
[2]
[1] 
						

							9-7
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COOLING SYSTEM
Disconnect the siphon hose [1] from the radiator.
Loosen the water hose band screws [2] and disconnect
the upper and lower water hoses [3].
Remove the radiator guard [4] by releasing the bosses
[5]
Remove the radiator mounting bolts [6] and radiator [7].
Installation is in the reverse order of removal.
Tighten the hose band screw to the specified range.
Fill the system with the recommended coolant (page 9-
5).
DISASSEMBLY/ASSEMBLY
Disassemble and assemble the radiator as following illustration.
[1]
[2]
[3]
[7][4]
[6]
[5]
0 – 1 mm (0 – 0.04 in)
1.0 N·m (0.1 kgf·m, 0.7 lbf·ft)
COOLING FAN
FAN MOTOR
FAN MOTOR SHROUD
2.7 N·m (0.3 kgf·m, 2.0 lbf·ft)
RADIATOR CAP
RADIATOR CAP SCREW8.5 N·m (0.9 kgf·m, 6.3 lbf·ft)
Align
RADIATOR