Yamaha EF1000A Service Manual

							SPECIAL TOOLS 
SPECIAL  TOOLS 
GEN 
INFO 
The following special tools are necessary for complete and accurate tune-up and assembly. Use 
only the appropriate special tools; this will help prevent damage caused by the use of 
inappropriate tools or improvised techniques. 
When placing an order, refer to the list provided below to avoid any mistakes. 
Tool No. 
YU-33294 
(90890-05158) 
YU-1047 
YU-03016  (90890-03016) 
YU-26900-9  (90890-03079) 
YU-33223 
(90890-03081) 
YU-33223-3 
(90890-04082) 
YU-03112 
(90890-03112) 
YU-8036-A 
(90890-03113) 
(90890-06754) 
Tool name I Usage 
Piston ring  compressor 
This tool is used  to compress the piston  rings 
when installing the piston. 
Rotor  shock 
puller set 
These 
tools are  used when removing the 
rotor. 
Cylinder gauge (35-60 mm) 
This gauge is used to measure the cylinder 
inside  diameter. 
Service  gauge (Thickness  gauge) 
This gauge is used to measure the valve 
clearance. 
Compression  gauge set CD 
Adaptor@ 
These tools are used to measure the engine 
compression. 
Pocket tester 
These 
instrument is invaluable for checking 
the electrical system. 
Indicative tachometer 
These 
instrument is invaluable for reading 
the engine  rpm. 
Ignition checker 
This 
instrument is  necessary for checking  the 
ignition system components. 
1-5 
Illustration 
CD  
						

							INTRODUCTION/MAINTENANCE INTERVALS CHART/ 
PERIODIC MAINTENANCE/LUBRICATION  INTERVALS 
PERIODIC INSPECTIONS AND ADJUSTMENTS 
INTRODUCTION 
This chapter includes  all information necessary to perform recommended  inspections and adjust­
ments.  These preventive  maintenance  procedures, 
if followed, will ensure more reliable machine 
operation  and a 
longer service life. The  need for costly  overhaul work will be greatly reduced.  This 
information applies to machines already in service as well as new machines that are  being  pre­
pared 
for sale.  All service  technicians should be familiar with this entire chapter. 
MAINTENANCE INTERVALS CHART 
Proper  periodic  maintenance  is important. Especially important are the maintenance services re­
lated to emissions control. These controls not only function to ensure cleaner air but are also vital to 
proper engine  operation  and maximum performance. In the following maintenance tables, the ser­
vices 
related to emissions control are  indicates  as ** in the chart. 
PERIODIC  MAINTENANCE/LUBRICATION  INTERVALS 
Pre-O~era-Initial Every 
No. 
Item Remarks tion c  eck 
1 month 3 months 6 months 12months (daily) or 20 hr or 50 hr or 100 hr or 300 hr 
** Check condition, adjust 1. Spark plug ~ap and clean. • eplace if necessary. 
** Check and adjust 2.* Valve  clearance when engine  is cold. • 
** Check breather  hose Crankcase 3.* breather system for cracks or damage. • Replace if necessary. 
** Check and adjust 
4.* Idle speed  engine idle speed. • 
Check for leakage. Retighten or replace • ** gasket if necessary. 5. Exhaust system Check spark arrester. Clean/replace if • necessary. 
** Check  oil level. • 6. Engine oil 
• Replace. • ** Clean.  Replace if 7. Air filter • necessary. 
8. Fuel filter Clean fuel ftetcock and fuel tank fi ter. • Replace if necessary. 
Check  fuel hose for 9. Fuel line cracks or damage. • Replace if necessary. 
** 10. Choke  lever  Check choke operation. • 
11. Cooling system Check for fan damage. • 
2-1  
						

							PERIODIC MAINTENANCE/LUBRICATION  INTERVALS 
Pre-O~era-Initial Every 
No. 
Item Remarks tion c  eck 
1 month 3 months 6 months 12months (daily) or 20 hr or 50 hr or 100 hr or 300 hr 
** Check  recoil starter • 12. Starting  system 
operation. 
** More frequency if 13. Decarbonizatior • necessary. 
14. Fittings/fasteners Check all fittings and 
fastners.  Correct if • necessary. 
2-2  
						

							ENGINE OIL 1•:gs 1 Q 1 
------------------------------------------------
700..()65 
-CD 
2-3 
ENGINE 
ENGINE  OIL 
Recommended oil: 
lA] VAMALUBE 4 (10W-30) or 
SAE 
10W-30 type SE 
[ID SAE #30 
[QI SAE #20 
[Q] SAE 10W 
Engine oil quantity: 
0.43 L (0.38 Imp qt, 0.45 US  qt) 
NOTE:------------------------
Recommended  engine oil classification: 
API 
Service SE or SF, if not available, 
SD. 
Oil  level inspection 
1. Check: 
•Oil level 
Oil level adjustment  steps: 
• Place the engine on a flat surface. 
• Warm up the engine for a few minutes. 
• Stop the engine. 
• Make  sure that the engine oil is between 
the upper and lower levels. Add oil  as 
necessary. 
G) Upper level 
(?) Lower level 
Oil  replacement 
1. Warm  up the  engine  oil for several  minutes. 
2. Place a receptacle under the engine. 
3. Remove: 
•Oil filler cap CD 
Tilting as shown the engine while the 
engine  oil draining.  
						

							1•:gs1d1 FUEL LINE INSPECTION/FUEL  PETCOCK/AIR FILTER _ . ~ _ 
+ 
:-..· : ..... 
2 
2-4 
4. Fill: 
•Engine oil 
Recommended  engine oil: 
0.43 
L (0,38 Imp qt, 0.45  US qt) 
Do not allow foreign material to enter the· 
crankcase. 
5. Install: 
•Oil filler cap 
FUEL LINE  INSPECTION 
1. Inspect: 
•Fuel hose G) 
•Fuel petcock ® 
Clacks/damage---+Replace. 
Poor connection---+Correct. 
FUEL PETCOCK 
Removal 
and inspection 
1. Turn the fuel petcock lever the C 
position. 
2. Inspect: 
•Fuel petcock  cup G) 
Connection---+Ciean. 
•Gasket  ® 
Da mage---+Replace. 
•Strainer ® 
Conta m 

i 
nation---+Ciea n. 
NOTE:--------------------------
Ciean the cup with solvent  and dry it off. 
3. Install: 
•Fuel 
petcock  cup 
I X 11.5 Nm (0.15 m•kg, 1.1 ft•lb) I 
AIR FILTER 
1. Remove: 
•Bolt G) 
•Air filter cover® 
•Air filter element® 
Refer to AIR FILTER.  
						

							IIANDSJP I ~ I AIR FILTER/MUFFLER ~ 
-------------------------------------------------------
• 
2-5 
2. Inspect: 
•Element 
Clogging~Wash the element in a 
solvent and dry it. 
Oil the element and squeeze out the 
excess oil. 
Damge~Rplace . 
• ~ Recommended oil: 
 U Form-air-filter oil or 
SAE #20 motor oil 
3. Inspect: 
•Air filter element 
•Air filter cover 
NOTE=--------------------------------------------------
Do not wiring out the element; this could 
cause it to tear. 
The engine should never be run without the 
air filter element; excessive piston and/or 
cylinder wear may result. 
MUFFLER 
1. Remove: 
•Muffler protector 
•Muffler 
Refer to MUFFLER . 
2. Remove: 
•Plate CD 
3. Clean: 
•Exhaust pipe 
•Muffler body@ 
To loosen carbon buildup tap on the 
muffler, in the area shown in the 
illustration. Then,  shake the carbon 
pieces out of the end of the muffler. 
Do 
not use a wire to the inside of the muffler 
or the nois damping material may come 
out, reducing the damping effect.  
						

							IIANDSJP I ~ I VALVE CLEARANCE ADJUSTMENT ~ 
-------------------------------------------------------
2-6 
VALVE CLEARANCE ADJUSTMENT 
NOTE=--------------------------
Valve clearance must be measured when the 
engine  is cool to touch. 
1. Remove: 
•Fuel tank 
•Breather hose CD 
•Air shroud (under)@ 
•Air shroud (upper)@ 
•Cylinder head cover@ 
•Spark plug @ 
2. Pull the starter rope until the piston 
touches the screwdriver. the piston is 
then  at 
TDC. 
3. Inspect: 
•Valve  clearance 
Out of specification---+Adjust. 
Standard valve clearance: 
Intake valve  (cold) 
0.1 mm (0.004 in) 
Exhaust 
valve  (cold) 
0.1 mm (0.004 in) 
Service gauge: 
VU-26900-9  (90890-03079) 
Valve clearance adjustment 
1. Turn the crankshaft until the piston 
reaches top dead center  (T.D.C.). 
2. Loosen the locknut CD and insert the 0.1 
mm (0.04 in) thickness gauge between 
the rocker arm and the valve top. 
3. Turn the adjuster @ in or out to obtain 
the proper valve clearance. Move the 
thickness gauge up and down to check 
for the proper resistance. 
Adjuster Resistance Valve  clearance 
Turn in Increase Decrease 
Turn 
out Decrease Increase 
4. Tighten the locknut CD 
ll"l
						

							VALVE CLEARANCE ADJUSTMENT/ l•:gs 1 ** 1 COMPRESSION  PRESSURE MEASUREMENT _ . ~ _ 
2-7 
5. Install: 
•Cylinder head cover gasket 
•Cylinder head cover CD 
•Air shroud (upper) ® 
•Air shroud (under)@ 
•Breather hose@ 
•Spark plug@ 
6. lighten: 
•Cylinder head cover 
1~19 Nm (0.9 m•kg, 6.5 ft•lb) I 
COMPRESSION  PRESSURE MEASUREMENT 
Insufficient compression pressure will result 
in performance loss and may indicate leaking 
valves 
or worm or damage piston  rings. 
1. Measure: 
•Valve clearance 
2. Warm up the engine for several minutes, 
then stop the engine. 
3. Remove: 
•Spark plug 
4. Connect: 
•Adapter CD 
•Compression gauge® 
Compression  gauge set: 
VU-33223 
(90890-03081) 
Adapter:  VU-33223-3 
(90890-04082) 
5. Measure: 
•Compression 
To measure the compression, pull the 
recoil starter until the needle stops 
rising  on the compression  gauge. 
Standard compression pressure: 
100 kPa (10 kg/cm2
, 14.2  psi) 
To prevent the sparking when cranking the 
engine, ground the spark plug wire.  
						

							CYLINDER HEAD DECARBONIZATION/ l•:gs 1 d 1 GOVERNOR ADJUSTMENT _ . ~ _ 
2-8 
Compression test steps (below minimum 
levels): • 
Squirt a few drops of oil into the 
cylinder. 
• 
Measure the compression  again 
Reading  Diagnosis 
If higher than • Worn cylinder, 
without oil piston and 
piston ring. 
If the same as • Defective piston, 
without oil ring(s), valve(s) 
and cylinder 
head gasket. 
• Improper valve 
timing and valve 
clearance. 
Compression test steps (above maximum 
levels): 
• 
Check the cylinder head, valve surfaces, 
and  piston 
crown for carbon  deposits. 
CYLINDER HEAD DECARBONIZATION 
1. Remove: 
•Carbon deposits 
Refer 
to CYLINDER HEAD INSPECTION 
GOVERNOR 
ADJUSTMENT 
1. Remove: 
•Fuel tank 
2. Adjust: 
•Governor 
Governor adjustment steps: 
1. Loosen the nut (j). 
2. Turn the governor arm @ 
counterclockwise until it stops. 
3. Turn the governor shaft@ 
counterclockwise  until it stops. 
4. Tighten the nut.  
						

							ENGINE SPEED ADJUSTMENT/ l•:gr 1 ~ 1 BREATHER HOSE INSPECTION/SPARK PLUG _ . ~ _ 
2-9 
ENGINE SPEED ADJUSTMENT 
1. Adjust: 
•Engine speed  (with no load) 
Engine  speed 
adjustment steps: 
1. Install the Tachometer  . 
2. Start the engine and let it warmup for a 
few minutes. 
3. Adjust the engine speed by turning the 
throttle stop screw CD in or out. 
Engine speed (with no load): 
60Hz 3,700-3,850 rpm 
Inductive tachometer: 
VU-8036-A (90890-03113) 
BREATHER HOSE INSPECTION 
1. Inspect: 
•Breather hose CD 
Clacks/damage-+Replace. 
Poor connection-+Correct. 
SPARK  PLUG 
1. Remove: 
•Spark plug 
Before removing the spark plug, use 
compressed air to clean the cylinder head 
cover to prevent dirt from falling the engine. 
2. Inspect: 
•Electrode CD 
Wear/damage-+Replace. 
•Insulator color@ 
3. Measure: 
•Plug gap@ 
Use a Wire gauge or thickness  gauge. 
Out of specification-+Replace. 
Spark plug gap: 
0,6-0,7 mm (0,024-0,028 in)