CAMSHAFT REMOVAL (After ’07)
Remove the cylinder head cover (page 9-7). Remove the crankshaft hole cap and O-ring.
“Д" MARK |
PUNCH MARK |
Turn the crankshaft clockwise to align the punch mark on the primary drive gear with the "Д" mark on the right crankcase cover.
Make sure the piston is at TDC (Top Dead Center) on the compression stroke.
This position can be obtained by confirming that there is slack in the rocker arm.
If there is no slack, rotate the crankshaft clockwise one full turn, and match up the punch mark on the primary drive gear with "Д" mark on the right crankcase cover again.
BOLT/SEALING WASHER |
Check that the index line on the cam sprocket aligns with the "Д" mark on the camshaft holder.
Remove the cam chain tensioner lifter bolt and sealing washer.
Insert the stopper tool into the cam chain tensioner lifter.
TENSIONER STOPPER |
Turn the stopper tool clockwise fully and lock the cam chain tensioner lifter by pushing the handle.
TOOL:
Tensioner stopper 070MG-0010100 or
07AMG-001A100 (U. S.A. only)
CAM SPROCKET |
Loosen the one cam sprocket bolt.
Be careful not to drop the bolts into the crankcase. Be careful not to drop the decompressor shaft and decompressor plunger. |
Turn the crankshaft clockwise one turn, and remove the other cam sprocket bolt.
Turn the crankshaft clockwise one turn again, and remove the remaining cam sprocket bolt.
Remove the cam sprocket from the camshaft and cam chain.
Suspend the cam chain with a piece of wire to prevent it from falling into the crankcase.
CAM CHAIN
CAMSHAFT HOLDER ASSEMBLY |
Make sure the piston is at TDC (Top Dead Center) on
the compression stroke.
Loosen the camshaft holder mounting bolts in a
crisscross pattern in two or three steps.
Remove the camshaft holder assembly.
• Valve lifters are installed into the camshaft holder assembly.
• The shims may stick to the inside of the valve lifters. Do not allow the shims to drop into the crankcase.
• Be careful not to drop the decompressor shaft and decompressor plunger.
BOLTS
VALVE |
LIFTERS |
Be sure to mark the valve lifters so they can be installed in their original positions. |
Remove the valve lifters from the camshaft holder assembly. |
SHAFT |
Remove the decompressor shaft and decompressor plunger.
PLUNGER |
Remove the stopper ring.
Thread a 6 mm bolt into the rocker arm shaft, and pull out the rocker arm shaft from the camshaft holder.
ROCKER ARM ROCKER ARM SHAFT |
Remove the rocker arm.
Remove the snap ring.
SNAP RING |
CAMSHAFT HOLDER |
Remove the camshaft from the camshaft holder.
Make sure the intake lobes are facing up when removing the camshaft from the holder to prevent damaging the intake lifter bores.
ROCKER ARM
If the camshaft contact surface of the rocker arm is damaged or abnormally worn, check the cam lobes for damage {page 9-20). |
Inspect the camshaft contact surface of the rocker arm for wear or damage.
Measure the rocker arm I. D.
SERVICE LIMIT: 12.05 mm (0.474 in)
ROCKER ARM SHAFT
Inspect the rocker arm shaft for wear or damage. Measure the rocker arm shaft O. D.
SERVICE LIMIT: 11.92 mm (0.469 in)
Calculate the rocker arm-to-shaft clearance. SERVICE LIMIT: 0.10 mm (0.004 in)
CAMSHAFT
Turn the outer race of the camshaft bearing with your finger.
The bearing should turn smoothly and quietly.
Also check that the bearing inner race fits tightly on the camshaft.
Replace the camshaft assembly if the bearing does not turn smoothly, quietly or if it fits loosely on the camshaft.
Check the cam lobe surfaces for scoring or evidence of insufficient lubricant.
Measure the height of each cam lobe.
SERVICE LIMITS:
IN: 36.890 mm (1.4524 in)
EX: 35.063 mm (1.3804 in)
NOTE:
Check the rocker arm if the cam lobe is worn or damage.
DECOMPRESSOR SHAFT/PLUNGER
SHAFT |
PLUNGER |
Check the decompressor shaft for bend or damage. Check the decompressor plunger for wear or damage.
Replace them if necessary.
CAM SPROCKET/DECOMPRESSOR WEIGHT/ SPRING
CAM SPROCKET DECOMPRESSOR WEIGHT |
SPRING |
Check the cam sprocket teeth for wear or damage. Check the decompressor weight for damage.
Check the spring for fatigue by moving the decompressor weight with your finger.
Replace the cam sprocket, decompressor weight and spring as an assembly if necessary.
CAMSHAFT HOLDER
Turn the inner race of the camshaft bearing with your finger.
The bearing should turn smoothly and quietly.
Also check that the bearing outer race fits tightly in the camshaft holder.
Remove and discard the bearing if the race does not turn smoothly, quietly, or if it fits loosely in the camshaft holder (page 9-21).
Check the valve lifter bore scoring, scratches or damage.
Measure each valve lifter bore I. D.
SERVICE LIMIT: 26.04 mm (1.025 in)
VALVE LIFTER
Check the valve lifter for scoring, scratches or damage.
Measure each valve lifter O. D.
SERVICE LIMIT: 25.97 mm (1.022 in)