Yamaha EF1000 Service Manual

STARTER WIRE ADJUSTMENT ~~~~j I C!it I 
STARTER WIRE ADJUSTMENT 
2-6 
1. Remove: 
•Rear cover 
•Side cover 1 
Adjustment  steps: 
a. Set the control lever to ON. 
b. Loosen the lock nut CD and nut@. 
c. Turn the nut @ clockwise ® until the 
open side of the lever ® becomes free 
from the stopper@. 
d. Loosen the nut @ 1/2 turn counterclock­
wise and secure the locknut G). 
e. Set the control lever to the 1-..1 position. 
f. Check whether the closed side of the 
lever@ contacts the stopper@. 
Contacts the...

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+ I I 1 
710-035 741-035 
r~g~l ~ 1 AIR FILTER/MUFFLER  _  _ ~ _ 
2-7 
AIR FILTER 
1. Remove: 
•Rear cover 
•Air filter cover CD 
•Air filter element~ 
2. Inspect: 
•Element 
Clogging~Wash the element in solvent and 
dry. 
Oil the element and  squeeze out excess oil. 
Damage~ Replace. 
Recommended Oil: 
3. Install: 
Foam-air-filter oil 
or 
SAE # 20 motor oil 
• Air filter  element 
• 
Air filter cover 
NOTE: --------------------------
Do not wring out the element. This could cause 
it to tear. 
The...

I
IANDSJP I ~~ I VALVE CLEARANCE ADJUSTMENT ~ 
-------------------------------------------------
2-8 
2. Decarbonize: 
1) Tap on the muffler in the area shown in 
the illustration. 
CAUTION: 
Dont use a wire to clean or the noise damp­
ing material may come out, reducing the 
damping effect. 
2) Shake out the loose carbon from car­
bon 
outlet CD of muffler. 
VALVE CLEARANCE ADJUSTMENT 
1. Remove: 
•Body panel 
•Air shroud 
•Gasket 
•Cylinder head cover 
•Spark plug 
2.  Measure: 
•Valve clearance 
Out...

I
IANDSJP 1 ~o• 1 COMPRESSION PRESSURE MEASUREMENT _ ~ 
-------------------------------------------------
2-9 
Valve clearance adjustment 
1. Turn the crankshaft until the piston reach­
es 
top dead center (T.D.C.). 
2. Loosen the locknut CD and insert the 0.1 
mm (0.004 in) Thickness Gauge YU-
26900-9  (90890-03079) between rocker 
arm and valve stem. 
3. Turn the adjuster @ in or out to obtain 
the proper Thickness Gauge resistance 
by pushing and pulling it. 
Adjuster Resistance Valve Clearance 
Turn...

CYLINDER HEAD/ 
BREATHER HOSE INSPECTION 
2-10 
Compression test steps (below minimum 
levels): 
•Squirt a few drops of oil into cylinder. 
•Measure compression  again 
Reading 
Diagnosis 
Higher than without •Worn cylinder, 
oil piston and piston 
rings 
Same as without oil •Defective piston, 
ring(s),  valve(s) and 
cylinder head gasket 
•Improper valve 
timing and valve 
clearance 
Compression test steps (above maximum 
levels): 
•  Check  cylinder head, valve surfaces,  or piston 
crown for carbon...

ENGINE SPEED ADJUSTMENT I 
GOVERNOR ADJUSTMENT 
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2-11 
ENGINE SPEED ADJUSTMENT 
1. Adjust: 
•Engine speed (with no load) 
Engine speed adjustment  steps: 
1. Install the Tachometer (YU-8036-A). 
2. Start the engine and warm up for a few 
minutes. 
3. Adjust the engine speed by turning the 
adjust screw CD in or out. 
{:} Engine speed (with no load): 
3,700-3,800 rpm 
GOVERNOR  ADJUSTMENT 
1. Remove: 
•Body panel 
•Fuel tank 
2. Adjust:...

____________ sP_A_R_K_P_Lu_G_I~IQI 
 , ,,~.._....._ __ 
2-12 
SPARK PLUG 
1. Remove: 
•Spark plug 
2. Inspect: 
•  Electrode 
CD 
Wear I Damage~ Replace. 
•Insulator  color 
~ 
3. Measure: 
•Plug gap@ 
Out of specification~ Regap. 
Use  a Wire  Gauge  or 
Feeler Gauge. 
Spark Plug Gap: 
0.6-0.7 mm (0.024-0.028 in) 
Clean the plug with a spark plug  cleaner if 
necessary. 
Standard  Spark Plug: 
BPR6HS 
(NGK) 
Before installing a  spark plug,  clean the gasket 
surface  and 
plug surface. 
4. Tighten:...

•llllull 
AIR FITER, CARBURATOR, MUFFLER ENG 8 
ENGINE 
AIR FILTER, CARBURATOR,  MUFFLER 
151.111 
3-1  

•I Ill nil 
AIR FITER, CARBURATOR,  MUFFLER ENG B 
JOB INSTRUCTION  CHART 
Order Job name/Parts name Oty Remarks 
Removal of Air filter, Carburator Remove the parts in order. 
and 
Muffler 
Body cover Refer to BODY COVER section 
in 
CHAPTER 2. 
Fuel tank Refer to FUEL TANK section 
in 
CHAPTER 2. 
1 Crankcase breather hose  1 
2 
Screw 2 
3 
Bolt 1 
4 
Air filter assmbly 1 
5 Air filter gasket 1 
6 Governor link rod  1 
7 
Carburetor assembly 1 
8 Carburetor cover 1 
9 Joint 1 
10 Intake manifold gasket...

ENGINE 
3-3 
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