ENGINE TOP END 5-1

Engine Top End

Table of Contents

Exploded View...................................	5-2
Exhaust System Identification ...........	5-6
Specifications ....................................	5-8
Special Tools and Sealant .................	5-9
Clean Air System...............................	5-11
Air Suction Valve Removal...........	5-11
Air Suction Valve Installation........	5-11
Air Suction Valve Inspection ........	5-12
Air Switching Valve Removal .......	5-12
Air Switching Valve Installation ....	5-12
Air Switching Valve Operation
Test............................................	5-13
Air Switching Valve Unit Test .......	5-13
Clean Air System Hose
Inspection..................................	5-13
Cylinder Head Cover .........................	5-14
Cylinder Head Cover Removal ....	5-14
Cylinder Head Cover Installation .	5-14
Camshaft Chain Tensioner ................	5-16
Camshaft Chain Tensioner
Removal ....................................	5-16
Camshaft Chain Tensioner
Installation .................................	5-17
Camshaft, Camshaft Chain ...............	5-18
Camshaft Removal ......................	5-18
Camshaft Installation ...................	5-19
Camshaft, Camshaft Cap Wear
Inspection..................................	5-23
Camshaft Runout Inspection........	5-24
Cam Wear Inspection ..................	5-24
Camshaft Chain Removal ............	5-24
Cylinder Head....................................	5-25

Cylinder Compression
Measurement ............................	5-25
Cylinder Head Removal ...............	5-26
Cylinder Head Installation ............	5-27
Cylinder Head Warp Inspection ...	5-28
Valves ................................................	5-29
Valve Clearance Inspection .........	5-29
Valve Removal .............................	5-29	5
Valve Installation ..........................	5-29
Valve Guide Removal ..................	5-29
Valve Guide Installation ...............	5-29
Valve-to-Guide Clearance
Measurement (Wobble
Method) .....................................	5-30
Valve Seat Inspection ..................	5-31
Valve Seat Repair ........................	5-31
Throttle Body Assy Holder.................	5-36
Throttle Body Assy Holder
Removal ....................................	5-36
Throttle Body Assy Holder
Installation .................................	5-36
Muffler................................................	5-37
Muffler Body Removal..................	5-37
Muffler Body Installation...............	5-38
Premuffler Chamber Removal .....	5-39
Premuffler Chamber Installation ..	5-40
Exhaust Pipe Removal.................	5-41
Exhaust Pipe Installation..............	5-42
Exhaust Butterfly Valve Cable
Removal ....................................	5-43
Exhaust Butterfly Valve Cable
Installation .................................	5-44

5-2 ENGINE TOP END

Exploded View

ENGINE TOP END 5-3

Exploded View

No.	Fastener		Torque			Remarks
		N·m	kgf·m		ft·lb
1	Air Suction Valve Cover Bolts	9.8	1.0		87 in·lb	L
2	Breather Hose Fitting	15	1.5		11	L
3	Camshaft Cap Bolts	12	1.2		106 in·lb	S
4	Camshaft Chain Tensioner Cap Bolt	20	2.0		15
5	Camshaft Chain Tensioner Mounting Bolts	11	1.1		97 in·lb
6	Camshaft Sprocket Bolts	15	1.5		11	L
7	Coolant Drain Bolt (Cylinder)	9.8	1.0		87 in·lb
8	Cylinder Head Bolts (M9)	39	4.0		29	MO, S
9	Cylinder Head Bolts (M6)	12	1.2		106 in·lb	S
10	Cylinder Head Cover Bolts	9.8	1.0		87 in·lb	S
11	Front Camshaft Chain Guide Bolt (Lower)	12	1.2		106 in·lb
12	Front Camshaft Chain Guide Bolt (Upper)	25	2.5		18
13	Spark Plugs	13	1.3		115 in·lb
14	Starter Clutch Bolt Cap	–	–		–	Hand-tighten
15	Throttle Body Assy Holder Bolts	12	1.2		106 in·lb	L
16	Throttle Body Assy Holder Clamp Bolts	2.9	0.30		26 in·lb
17	Timing Inspection Cap	–	–		–	Hand-tighten
18	Upper Camshaft Chain Guide Bolts	12	1.2		106 in·lb	S
19	Water Passage Plugs	19.6	2.0		14	L

EO: Apply engine oil.

G: Apply grease.

L:Apply a non-permanent locking agent.

M:Apply molybdenum disulfide grease. MO: Apply molybdenum disulfide oil solution.

(mixture of the engine oil and molybdenum disulfide grease in a weight ratio 10:1)

R:Replacement Parts

S:Follow the specified tightening sequence.

SS:Apply silicone sealant.

5-4 ENGINE TOP END

Exploded View

ENGINE TOP END 5-5

Exploded View

	No.	Fastener		Torque		Remarks
			N·m	kgf·m	ft·lb
	1	Exhaust Butterfly Valve Cable Adjuster Locknuts	6.9	0.70	61 in·lb
	2	Exhaust Butterfly Valve Cable Locknuts	7.0	0.71	62 in·lb
	3	Exhaust Pipe Clamp Bolt	17	1.7	13
	4	Exhaust Pipe Guard Bolts	6.9	0.70	61 in·lb
	5	Exhaust Pipe Holder Nuts	17	1.7	13
	6	Muffler Body Clamp Bolt	17	1.7	13
	7	Muffler Body Cover Bolts	7.0	0.71	62 in·lb
	8	Muffler Body Mounting Bolt	25	2.5	18
	9	Muffler Body Rear Cover Bolts	7.0	0.71	62 in·lb
	10	Premuffler Chamber Bracket Bolt	35	3.6	26
	11	Premuffler Chamber Guard Bolts	6.9	0.70	61 in·lb
	12	Premuffler Chamber Mounting Bolt	35	3.6	26

R: Replacement Parts