Yamaha EF1000A Service Manual

							SPARK PLUG/ A.C. PROTECTOR INSPECTION/ 1~:gs 
1 
** 1 ENGINE SWITCH INSPECTION/ A. C. RECEPTACLE INSPECTION .  . ~ . 
ION) 
~ 
o(;) 
(OFF) 
If necessary, clean the spark plug with a spark 
plug  cleaner. 
Standard spark plug: 
Resistored spark plug : BPR6HS 
Before installing the spark plug, clean the 
gasket  surface  and plug surface. 
4. Tighten: 
•Spark plug CD 
ll'l!:"~.....,lr2~0-::-N:-m____,(2-.0-m-·-:-kg-,-,-4 ~ft-·lb--,) I 
NOTE:-------------------------
Finger tighten CD the spark plug before 
torquing@, to prevent thread damage. 
A.C. PROTECTOR  INSPECTION 
1. Check the protector ON position. 
2. Connect the pocket tester (A.C.120 V) to 
the receptacle and inspect the output the 
A.C. current. 
3. The protector OFF position, does not 
output the A.C. current. 
ENGINE  SWITCH  INSPECTION 
1. Check the switch I(ON) position. 
2. Start the engine. 
2-10 
3. Inspect: 
•Engine switch operation 
If the switch position turn O(OFF), 
stop the engine. 
Engine  switch is 
not operation~Replace. 
A.C. RECEPTACLE  INSPECTION 
1. Inspect: 
•A.C.  receptacle 
CD 
Clacks/damage~Replace. 
Poor connection~Correct.  
						

							ENGINE OVER HAUL ENG 
ENGINE 
ENGINE OVERHAUL 
MUFFLER PROTECTOR, FUEL TANK AND MUFFLER 
IELft ___ (Sia Nm (0:6 m•kg, 4.3 ft-lb)l 
~ [ 17 Nm (0. 7 m•kg, 5.1 ft-lb) I @ @ I 
0 
JOB INSTRUCTION CHART 
Order Job name/Parts name 
Muffler protector, fuel tank and 
muffler removal 
1 Muffler protector 
2 
Fuel hose 
3 Fuel tank 
4 Muffler assembly 
5  Gasket (muffler) 
2 
7 Nm (0.7 m•kg, 5.1 ft-lb) 
Oty Remarks 
Remove 
the parts in the order below. 
1 NOTE: Disconnect  the fuel  hose,  turn the fuel 
1  petcock position  to the 
C position. 
1  Refer 
to MUFFLER. 
1 NOTE: Be sure install  the gasket,  projection side 
to upward. 
1 
For installation, reverse the removal 
procedure. 
3-1  
						

							ENG 
AIR ALTER, CARBURE ENGINE OVER HAUL 
TOR AND CONTROL BOX 
JOB INSTRUCTION CHART 
Order 
1 
2 
3 
4 
5 
6 
7 
8 
A Job name/Parts name 
•r filter, carburetor and 
c Fontlrol box removal 
ue tank 
B~eather hose 
Air filter assembl 
Gasket (air filter) y 
Governor link rod 
Carburetor assembl 
JGa_sket (carburetor) y 
omt 
Control box 
1 
1 
1 
1 
1 
1 
1 
1 
3-2  Remarks 
Remove the . parts m the order below 
Refer to MUF · FUEL TANK A~DLER PROTECTOR MUFFLER. I 
Refer to CARBURETOR 
NOTE: Disconnect 
the 
F  . 
before  control ~~uplers and connectors 
or mstallation x removal.  , procedure. reverse the removal  
						

							CYLINDER HEAD COVER AND CYLINDER HEAD ENG 
CYLINDER HEAD COVER AND CYLINDER HEAD 
3 
JOB INSTRUCTION  CHART 
Order Job name/Parts name Oty 
Cylinder head cover  and 
cylinder head removal 
Muffler protector , muffler and 
fuel tank 
Recoil starter 
Air filter and carburetor 
1 Spark  plug/Plug  cap 1/1 
2 Air shroud upper 1 
3 
Air shroud under 1 
4 
Cylinder head cover 1/1 
5 Gasket (cylinder head  cover) 1 
6 
Cylinder head assembly 1 
7 
Gasket (cylinder head) 1 
8 Dowel pins 1 
9 Push  rods 1 
3-3 
l\l2o Nm (2.0 m•kg, 14 ft-lb) I 
1 
m 
Remarks 
smm 
Remove the parts  in the order below. 
Refer to MUFFLER PROTECTOR, 
FUEL TANK AND MUFFLER. 
Refer 
to RECOIL STARTER. 
Refer to AIR FILTER. 
Refer to Cylinder head installation. 
For installation, reverse the removal 
procedure.  
						

							IIANDSJP I d I CYLINDER HEAD COVER AND CYLINDER HEAD . ~ _ 
---------------------------------------------------
3-4 
INSPECTION 
Cylinder head 
1. Remove: 
•Carbon deposits 
Use  a rounded  scraper. 
NOTE=------------------------­
Be careful to the cylinder head inside when 
decarbonaizing. 
2. Inspect: 
•Cylinder head 
Ware/Damage~Replace. 
3. Measure: 
•Cylinder head wrappage 
Exceeds allowable limit~Replace. 
Wrappage limit: 
0.1 mm (0,004 in) 
INSTALLATION 
1. Install: 
•Dowel pins 
•Cylinder head gasket 1m 
•Cylinder head assembly 
1~111 Nm (1.1 m•kg, 8.0 ft•lb) 
NOTE:--------------------------
Follow the tightening sequence.  
						

							ROCKER ARMS, VALVES AND VALVE SPRINGS ENG 
ROCKER ARMS, VALVES AND VALVE SPRINGS 
1 
m 
JOB INSTRUCTION CHART 
Order Job name/Parts name 
Rocker 
arms ,  valves  and 
valve 
springs removal 
Cylinder head assembly 
1 Locknuts/Adjusters 
2 Rocker  arms 
3 Valve spring seats 
4 Valve springs 
5 Push rod guide 
6 Valve (intake) 
7 Valve (exhaust) 
Qty Remarks 
Remove 
the parts  in the order below. 
Refer to CYLINDER HEAD. 
2/2 2  -J Refer to Valve and valve spring 2 
2  -installation. 
1 
1 
1 
For installation, reverse  the removal 
procedure. 
3-5 
7  
						

							ROCKER ARMS, VALVES AND VALVE SPRINGS ENG 
@ 
3-6 
REMOVAL 
1. Remove: 
•Valve spring seat 
						

							ROCKER ARMS, VALVES AND VALVE SPRINGS ENG 
302-005 
3-7 
3. Measure: 
•Valve stem bend 
Out of specification--+Replace. 
Valve stem bend limit: 
0.01 mm (0.0004 in) 
4. Measure: 
•Valve spring  free length® 
Out of specification--+Replace. 
Valve spring free length: 
27.4 mm (1.0787 in) 
limit: 
24.4 mm (0.9606 in) 
5. Measure: 
•Valve spring tilt® 
Use a square 
Out of specification--+Replace. 
Valve spring tilt limit: 
0.8 mm (0.03 in) 
6. Measure: 
•Valve spring  contact  surface 
Out of specification--+Replace. 
Rocker arm 
1. Inspect: 
•Rocker 
arm 
Cracks/Ware/Damage--+Replace.  
						

							ROCKER ARMS, VALVES AND VALVE SPRINGS ENG 
302-011 
3-8 
Push rod 
1. Measure: 
• Push rod bend 
Roll on V-block 
Exceeds vending limit---+Replace. 
Push rod  vend limit: 
0.5 
mm (0.02 in) 
Valve seat 
1. Decarbinaized to the valve face  and valve 
seat. 
2. Measure: 
•Valve contact width® 
Poor seating---+Lap. 
Valve contact with: 
0. 7 mm (0.027 in) 
limit: 
1.2 mm (0.047 in) 
3. Measure: 
•Valve seat contact width® 
Poor seating---+Lap. 
Valve seat  contact  with: 
0. 7 mm (0.027 in) 
limit: 
1.2 mm (0.047 in) 
Valve seat assembly  lapping 
1. Apply: 
•Coarse lapping compound (a small 
amount to the valve face) 
2. Position: 
•Valve 
(in the cylinder head) 
3. Rotate: 
•Valve 
Turn until the valve and seat  are evenly 
polished, then clean off the remaining 
compound. 
4. Repeat the above steps with a fine 
compound and continue lapping until the 
valve face  has a completely smooth 
surface.  
						

							ROCKER ARMS, VALVES AND VALVE SPRINGS ENG 
5. Remove: 
•Compound 
(from the valve face) 
6. Apply: 
•Mechanic]s bluing dye (Dykem) CD 
(to the valve face  and seat) 
7. Rotate: 
•Valve 
302-017 The valve must make full seat contact. 
L-------------------1 This is indicated by a gray surface all 
3-9 
around the valve face where the bluing 
was removed. 
8. Apply: 
•Solvent 
(into  each  intake  and exhaust  port) 
Leakage 
past valve seat---+Repeat valve 
lapping until the seal is complete. 
NOTE:--------------------------
Pour the solvent into the intake and exhaust 
ports only after completion of all the valve 
work and assembly of the cylinder head.