Engine Overhaul - Yamaha XT550J Service Manual

CHAPTER 3. ENGINE OVERHAUL
ENGINE REMOVAL . .......................................... 3-1
A.
Preparation for Removal ...................................... 3-1
B. Seat and Fuel Tank ......................................... 3-1
C. Muffler, Footrest, and Brake Pedal ............................. 3-2
D. Oil Hoses ................................................. 3-2
E. Carburetor ................................................ 3-3
F. Drive Chain and Drive Sprocket ................................ 3-3
G. Engine Mounting Bolts ....................................... 3-4
DISASSEMBLY . .............................................. 3-5
A.
Cylinder Head Cover ........................................ 3-5
B. Cylinder Head ............................................. 3-5
C. Cylinder .............. . ................................... 3-6
D. Piston Pin and Piston ........................................ 3-6
E. Kick Crank ................................................ 3-7
F. C.D.I. Rotor ............................................... 3-7
G. Cam Chain and Guide Stopper ................................. 3-7
H. Crankcase Cover (Right) ..................................... 3-7
I. Clutch Assembly and Drive Gear ............................... 3-8
J. Clutch Push Lever Axle ...................................... 3-8
K. Oil Pump Assembly ......................................... 3-9
L. Kick Axle Assembly ......................................... 3-9
M. Change Shaft Assembly ...................................... 3-9
N. Balancer Gear .............................................. 3-9
O. Crankcase ................................ . .............. 3-10
P. Transmission ............................................. 3-10
Q.
Crankshaft ............................................... 3-11
R. Oil Strainer Assem bly ....................................... 3-11
INSPECTION AND REPAIRING ................................ 3-12
A. Cylinder Head Cover ....................................... 3-12
B. Cylinder Head ............................................ 3-12
C. Valves, Valve Guides, Valve Seats, and Valve Springs .............. 3-13
D. Rocker Arms and Rocker Arm Shafts .......................... 3-17
E. Camshafts, Cam Chains, and Cam Sprockets ..................... 3-18
F. Cylinder ................................................. 3-19
G. Piston and Piston Rings ..................................... 3-19
H. Crankshaft and Connecting Rod ............................... 3-21
I. Oil Pump ................................................ 3-23
J. Primary Drive ............................................. 3-23
K. Clutch .................................................. 3-23
L. Transmission ............................................. 3-25
M. Kick Starter .............................................. 3-26
N.
O.
Bearings and Oil Seals ...................................... 3-26
Installation ............................................... 3-27