Makita PM7651H Manual

March 2016
TECHNICAL INFORMATION
OFFICIAL USE
for ASC & Sales Shop
Specification
Engine
Max output: kW (PS)
Max torque: N·m
Specification Model
Fuel
Type
Displacement: mL (cu.in.)
Dry weight*3: kg (lbs)
2.7 (3.7) at 7,000 rpm
Max rotation speed at no load: min-ı= rpm 7,400
4.4 at 5,000 rpm
4-stroke
PM7651H
YesCompliance with exhaust emission regulations
14.1 (31.1)
Engine oil SAE10W-30 oil,
Class SF or higher of API Classification
75.6 (4.61)
Straight unleaded gasoline*1(E0 to E10)
*1 "Straight" means "not mixed with engine oil".
*2 With nozzle
*3 With Straight pipe 380, without Hip belt
DiaphragmCarburetor
YesRotation limiter
Model PM7651H is a Petrol mist blower powered by 75.6mL
4-stroke engine, and developed based on the current model PM7650H.
The modifications from the current model PM7650H are as follows:
● Compliance with EU standards
• Lock-off button on the handle
• Without lock-on function for throttle
• Non-removable tank cap with retaining strap
• Gap between strainer and tank is 2mm or less
● Throttle lever with 3-stage switching function
● Anti-static throttle lever
Dimensions: mm (")
Width (W)
Height (H)
Length (L)
440 (17-1/4)
420 (16-1/2)
595 (23-1/2)
CONCEPT AND MAIN APPLICATIONS H
W
L
Yes (Mechanical)
Starting system
Decompression
Easy start
(Spring-assisted recoil starter) No
CMR6ASpark plug
YesPrimer pump
1.8 (61)Fuel tank capacity: L (US oz)
15.0 (507)Solution tank capacity: L (US oz)
16.0 (52)Max spray range (horizontal): m (ft)
85Max air speed: m/s
14.1 (497)Max air volume*2: m³/min
1 / 41
Petrol Mist Blower
Model No. PM7651H
Description

OFFICIAL USE
for ASC & Sales Shop
2 / 41
Standard equipment
Oil bottle*1
Box wrench
Hand strap
Flexible pipe
Hose clamp 76 (x4)
Hose clamp 100 (x1)
Hip belt set*2
Straight pipe 630*2
Straight pipe 380*2
Bent pipe 630*2
End pipe 200*2
End pipe 450*2
Flat pipe*2
Nozzle 0.8*2
Tube 10-500*2
*1 With engine oil contained for some countries
*2 Depends on destinations.
Note: The standard equipment may vary by country or model variation.
Optional accessories
Straight pipe 630
Straight pipe 380
Bent pipe 630
End pipe 200
End pipe 450
Flat pipe
Hose clamp set
Oil bottle set (inc. 220mL engine oil)
Air cleaner element
Nozzle 0.8
Nozzle 0.7
Nozzle 0.5
Hip belt set
O ring set

1INDEX
1INDEX.......................................................................................................................................................................................... 3
2CAUTION .................................................................................................................................................................................... 5
3HANDLING OF GASKET.......................................................................................................................................................... 5
4NECESSARY REPAIRING TOOLS ........................................................................................................................................... 5
5LUBRICANT AND ADHESIVE APPLICATION ...................................................................................................................... 6
5-1 Several sections.................................................................................................................................................................... 6
5-2 Cylinder block section.......................................................................................................................................................... 7
6REPAIR ........................................................................................................................................................................................ 8
6-1 Nozzle section...................................................................................................................................................................... 8
6-1-1 Disassembling ............................................................................................................................................................. 8
6-1-2 Assembling.................................................................................................................................................................. 8
6-2 Cock section......................................................................................................................................................................... 9
6-2-1 Disassembling ............................................................................................................................................................. 9
6-2-2 Assembling................................................................................................................................................................ 10
6-3 Pipe section ........................................................................................................................................................................ 11
6-3-1 Disassembling ........................................................................................................................................................... 11
6-3-2 Assembling................................................................................................................................................................ 11
6-4 Engine cover complete, Recoil, Fuel tank.......................................................................................................................... 12
6-4-1 Disassembling ........................................................................................................................................................... 12
6-4-2 Assembling................................................................................................................................................................ 13
6-5 Control cable ...................................................................................................................................................................... 14
6-5-1 Disassembling ........................................................................................................................................................... 14
6-5-2 Assembling................................................................................................................................................................ 14
6-6 Tank complete (Chemical tank) ......................................................................................................................................... 15
6-6-1 Disassembling ........................................................................................................................................................... 15
6-6-2 Assembling................................................................................................................................................................ 16
6-7 Blower section.................................................................................................................................................................... 17
6-7-1 Disassembling ........................................................................................................................................................... 17
6-7-2 Assembling................................................................................................................................................................ 18
6-8 Frame section ..................................................................................................................................................................... 19
6-8-1 Disassembling ........................................................................................................................................................... 19
6-8-2 Assembling................................................................................................................................................................ 19
6-9 Ignition system................................................................................................................................................................... 20
6-9-1 Checking plug cap..................................................................................................................................................... 20
6-9-2 Checking Spark plug ................................................................................................................................................. 20
6-9-3 Checking of Ignition coil........................................................................................................................................... 21
6-9-4 Checking of Ignition coil (cont.) ............................................................................................................................... 22
6-9-5 Removing Ignition coil.............................................................................................................................................. 23
6-9-6 Mounting Ignition coil............................................................................................................................................... 23
6-9-7 Removing Flywheel complete................................................................................................................................... 24
6-9-8 Mounting Flywheel complete.................................................................................................................................... 24
6-10 Starter unit.......................................................................................................................................................................... 25
6-10-1 Disassembling Recoil starter ..................................................................................................................................... 25
6-10-2 Assembling Recoil starter.......................................................................................................................................... 25
6-11 Carburetor section .............................................................................................................................................................. 27
6-11-1 Removing Carburetor................................................................................................................................................ 27
6-11-2 Disassembling/Cleaning Carburetor.......................................................................................................................... 27
6-11-3 Assembling Carburetor ............................................................................................................................................. 29
6-11-4 Vacuum leak test of Carburetor ................................................................................................................................. 29
6-11-5 Mounting Carburetor................................................................................................................................................. 29
6-11-6 Adjusting Carburetor................................................................................................................................................. 30
6-12 Stop switch......................................................................................................................................................................... 31
6-12-1 Checking Stop switch................................................................................................................................................ 31
6-13 Fuel tube section ................................................................................................................................................................ 31
6-13-1 Fuel tube routing ....................................................................................................................................................... 31
6-14 Engine block ...................................................................................................................................................................... 32
6-14-1 Engine block section ................................................................................................................................................. 32
3 / 41

6-15 Engine block ...................................................................................................................................................................... 37
6-15-1 Cylinder head section ................................................................................................................................................ 37
6-15-2 Adjustment of valve clearance .................................................................................................................................. 39
6-15-3 Assembling of Muffler exhaust and Insulator complete............................................................................................ 39
6-16 Final check......................................................................................................................................................................... 40
7TIGHTENING TORQUE SPECIFICATIONS .......................................................................................................................... 41
4 / 41

2CAUTION
Repair the machine in accordance with “Instruction manual” or “Safety instructions.
Follow the instructions described below in advance before repairing:
· Wear gloves.
· When the engine is hot from use, cool down the engine enough or you can get burned.
· Remove remaining fuel from Fuel tank and Carburetor completely. [FLAMMABLE MATERIAL KEEP FIR E AWAY ]
· Remove Spark plug cap from Spark plug.
· Repair the engine on a stable workbench and in a clean workplace kept as free of dust and debris as possible.
· In order to avoid wrong reassembly, draw or write down where and how the parts are assembled, and what are the parts.
It is also recommended to have boxes ready to keep disassembled parts by group.
· Handle the disassembled parts carefully. Clean and wash them properly.
· If some bolts and screws are too tight, use Impact driver.
· Tighten the bolts and the screws to the specified torque as shown in "7 TIGHTENING TORQUE SPECIFICATIONS".
· Each time after you mounted a main part of the engine such as the piston, check if it moves smoothly without abnormal noise by
manually turning the crankshaft.
· After completion of reassembly, check for loose parts or abnormal noise and vibration by manually turning the crankshaft.
3HANDLING OF GASKET
Once Gasket is removed:
[1] Clean up the mating surfaces where the gasket was installed to maintain its sealing performance.
[2] Replace the removed Gaskets with new ones. Do not reuse them.
4NECESSARY REPAIRING TOOLS
Code No.
Description
Use for
1R070
Tachometer
measuring engine rpm
1R127
Air density tester
diagnosing Carburetor
1R181
Ignition checker
diagnosing Ignition coil
1R223
Torque wrench shaft 20-90N·m
tightening Nut that holds Flywheel
1R268
Spring pin extractor M3
disassembling Band
1R286
Round bar for Arbor 12-50
removing Piston pin
1R288
Screwdriver magnetizer
removing Cotter
1R364
Flywheel puller
removing Flywheel
1R366
Feeler gauge set
adjusting Ignition coil, Spark plug, Rocker arm
1R372
Crank shaft lock bolt M10
holding Flywheel
1R389
Cotter removal attachment
assembling/removing Va l v e (used together with 1R005)
1R402-A
Digital tester
diagnosing Stop switch and Ignition coil
-
Hex socket bit 14
mounting/removing Flywheel
-
Wire brush
cleaning Spark plug
5 / 41

5LUBRICANT AND ADHESIVE APPLICATION
Apply the following lubricants and adhesives.
5-1 Several sections
Lubricant
Amount
Makita grease FA No.2
a little
4-stroke engine oil
a little
Outer circumference
of O ring 93
Elbow
Spiral spring
Any lubricants
are available.
Nozzle cap
Top adapter
Diffusion
cover
Intake valve
Exhaust valve
Retainer
Cotter
Compression
spring 11
Cylinder head
complete
Valve guide
Cam lifter R
with a cross bar
Camgear assy
Pin 5
Note: short
Cam lifter L
Pin 5
Note: long
Fig. 5-1-1
Fig. 5-1-2
Fig. 5-1-3
Fig. 5-1-4
Fig. 5-1-5
6 / 41

5-2 Cylinder block section
Use parts cleaner or the like to remove grease from the mating surface of Crankcase to Cylinder block, and then apply ThreeBond
1215 or 1216 as shown below.
Oil route
Note: ThreeBond 1215 or 1216
should not be come into here.
Surface where
ThreeBond 1215 or
1216 should be applied
Fig. 5-2-1
7 / 41

6REPAIR
6-1 Nozzle section
6-1-1 Disassembling
6-1-2 Assembling
Assemble by reversing the disassembly procedure.
Fig. 6-1-1-1
[1] Remove Hose clamp 14 with remove Tube 10-500 (or Tube 10-250) from Nozzle adapter complete.
[2] Remove M5x18 Pan head screw to release Hose clamp 76, and remove Nozzle adapter complete, Straight pipe and Top
adapter.
[3] Remove Diffusion cover from Top adapter by turning it counterclockwise.
Fig. 6-1-1-2
[4] Remove 4x20 Tapping screw, and remove Sleeve 25
from Top adapter.
Fig. 6-1-1-3
[5] Remove O ring 28 from Sleeve 25.
Top adapter
Sleeve 25
4x20 Tapping screw
Sleeve 25
O ring 28
Fig. 6-1-1-4
[6] Remove Nozzle 4.5 from Nozzle adapter complete with
a slotted screwdriver.
Nozzle 4.5
Fig. 6-1-1-5
[7] Remove PT 3x10 Tapping screw bind, and remove
Nozzle cap from Nozzle adapter complete.
[8] Remove O-ring 12 from Nozzle cap.
[9] Remove Pin 5.5 and Compression spring 3 from Nozzle
adapter complete.
Apply Makita grease FA
No.2.
Top adapter
Diffusion cover
M5x18 Pan head screw
Nozzle adapter
complete
Straight pipe
Hose clamp 14
Tube 10-500 or Tube 10-250
Hose clamp
76
Compression
spring 3
Nozzle cap
PT 3x10 Tapping
screw bind
O-ring 12
Apply Makita grease
FA No.2.
Pin 5.5
Nozzle adapter
complete
Nozzle adapter
complete
8 / 41

6-2 Cock section
6-2-1 Disassembling
Fig. 6-2-1-1
[1] Release two Hose clamps 76, and remove Cock body
and Strainer case.
Cock body
Front side
Strainer case
Hose clamp 76 (2 pcs.)
Fig. 6-2-1-2
[2] The components of Cock section are as follows:
Cock
body
Strainer case
3x16 Tapping screw
(2 pcs.)
O-ring 12
Cap hose
Joint strainer
Pliers
Tube 10-500
Hose clamp 14
Hose clamp 14
Hose clamp 14
Tube 10-750
Fig. 6-2-1-3
[3] Remove 4x18 Tapping screw, and remove Cock lever.
4x18 Tapping screw
Cock lever
Cock
Fig. 6-2-1-4
[4] Screw 4x18 Tapping screw into Cock, and remove Cock
by holding it with long-nose pliers.
[5] Remove O-ring 9.
O-ring 9
Cock
4x18 Tapping screw
9 / 41

6-2-2 Assembling
[1] Assemble by reversing the disassembly procedure.
Fig. 6-2-2-1
[2] Apply Makita grease FA No.2 a little on the
outer circumference of Cock and O-ring 9.
Fig. 6-2-2-2
[3] Insert Cock into Cock body and turn it with pliers as shown below,
and assemble Cock lever with 4x18 Tapping screw.
O-ring 9
Cock
(1)
(2)
(3)
4x18 Tapping screw
Cock lever
Fig. 6-2-2-3
[4] Assemble Cock section to Straight pipe.
Straight pipe
Cock section
10 / 41