Makita EH7500S User Manual

T

Model No.

ECHNICAL INFORMATION

EH7500S

PRODUCT

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Description

Petrol Hedge Trimmer

CONCEPT AND MAIN APPLICATIONS

Model EH7500S is a 22.2cm³ 2-stroke petrol hedge trimmer
with single-sided blade in compliance with all known exhaust
emission regulations, featuring extra light design with further
improvements in noise, vibration and handling compared with
our current models.
Especially, the lightweight design is outstanding.

4.7kg (10.4lbs) dry weight is the world’s lightest among all petrol
hedge trimmers in compliance with any exhaust emission regulation
as of February, 2010.

Specification

Specifications

Type

Engine Displacement: cm³

Fuel

In compliance with main exhaust emission regulations;
CARB Tier 3, EPA Phase 2, EU Stage 2

Max. output power: kW (PS) 0.68 (1.0) [at 7,500 min.ˉ¹]

Max. torque: N.m
Stroke rate at No load: min.

Max. cutting capacity: mm (") 728 (25-5/8)

Carburetor

Clutch Yes

Rotation limiter Yes

Type

Length: mm (")

Blade

Max. branch diameter

Net weight*2: kg (lbs)

*1: Indicates maximum diameter of the branch that can be received
between adjacent two blade teeth. (See the figure on right.)
*2: Dry weight

Cutting teeth
Thickness: mm (")

Blade drive mechanism
Tooth spacing: mm (")

ˉ¹ = spm (stroke pre minute)

*1: mm (")

Model

EH7500S

2-stroke

22.2

Mixed gasoline

Yes

0.9 [at 6,000 min.ˉ¹]
4,390

0.4 (13.5)Fuel tank capacity: L (US oz)

Diaphragm

Recoil starterStarting system

YesPrimer pump

Single-sided

750 (29-1/2)

with 3 sharpened edges

2.3 (3/32)

Connecting rod drive

35 (1-3/8)

21.5 (7/8)

4.7 (10.4)

Dimensions: mm (")

Length (L) 1,150 (45-1/4)

Width (W)

Height (H)

323 (12-3/4)

212 (8-3/8)

Standard equipment

Blade cover .................... 1

Socket wrench ................ 1

Hex wrench .................... 1

Note: The standard equipment for the tool
shown above may vary by country.

Optional accessories

Chip receiver set

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Repair

CAUTION: Repair the machine in accordance with “Instruction manual” or “Safety instructions”.

< Note in repair>

* Repair the tool always with gloved hand
* Blades must be covered by Blade cover
* Cool down the engin first before repairing to avoid a skin burn.
* Remove all fuels from fuel tank and carburetor. Avoid any fire from the work shop.
* Repair the tool on the stable work table and keep dust out.
* Record where and how the parts were assembled to avoid mis-assembling.
Assort and reserve the dismantled parts in the box by section.
* The dismantled parts must be treated carefully and washed clean before reassembling.
* Use Impact driver in case bolts or screws can not be loosen by hand.
* The bolts or screws must be tightened to the designated fastening torque.
* Check the movement, sound and alignment of the main parts just after assembled.
* Replace the removed gasket with the new one.

[1] NECESSARY REPAIRING TOOLS

Code No. Description Used for

1R024 Press tool removing Spur gear 9

1R127 Air density tester checking air leakage in Carburetor

1R170 T type hex wrench 3-127 removing / tightening M4 Hex socket head bolt

1R171 T type hex wrench 4-130 removing / tightening M5 Hex socket head bolt

1R229 1/4” hex shank bit removing / tightening Engine section

1R364 Fly wheel puller removing Fly wheel

1R366 Feeler gauge set adjusting a proper gap of ignition coil, Spark plug, Shear blade assembly

1R371 Clutch removing tool removing Clutch

1R373

1R374

Clutch drum removing tool

Pinion gear holding Jig

Hex socket bit 10

Wire brush cleaning Spark plug

removing Clutch drum

fixing Spur gear 9

removing Fly wheel

[2] LUBRICATION

Apply Makita Grease N. No.2 to Spiral spring for recoil starter (approx. 2g) and Gear room (approx. 40g).

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Repair

[3] DISASSEMBLY/ASSEMBLY
[3] -1. Engine section

DISASSEMBLING

(1) Disconnect Bullet terminal from the Lead wire of Ignition coil. (Fig. 1)
(2) Remove Air cleaner cover and disconnect control cable from the swivel of carburetor.
Remove Control cable from cable bracket. (Fig. 2)
(3) Remove three bolts to separate engine section. Grounding lead wire is fastened with one of the three bolts. (Fig. 3)

Fig. 1 Fig. 2

Bullet terminal

Fig. 3

Grounding lead wire

ASSEMBLING

(1) Assemble engine section to the Gear housing.
Note: • Do not to pinch the Lead wires between Engine section and Gear housing.

• Make sure to fasten the terminal of Grounding lead wire with one of three Hex socket head bolts.
(2) Fix Control cable along with Adjust screw in the Cable bracket by clamping it with a Nut.
Hook the Control cable end on the Swivel of Carburetor.
Note: Adjust the Cable tension with a 1 - 2 mm play.
(3) Connect Bullet terminals. (Fig. 1)

Control cable

Repair

[3] DISASSEMBLY/ASSEMBLY
[3] -2. Clutch Section

DISASSEMBLING

By using impact driver, Clutch can be loosened without holding Piston by utilizing air pressure in the cylinder.
In order to utilize this air pressure resistant, do not remove Spark plug in this step.
(1) Separate Engine section from Gear housing. (Figs. 1, 2 and 3)
(2) Remove Clutch. (Fig. 4)

Fig. 4

Caution:

Remove Plug cap to avoid
an accidental start of engine.

1. Fit 1R371 to Clutch.

2. Fix 19mm Hex socket bit to
Impact driver.

3. Turn the Clutch clockwise
with Impact driver.

4. Now, the Clutch is removed
from Crankshaft.

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1R371

Clutch

ASSEMBLING

(1) Drive the Clutch to Crankshaft counterclockwise by hand so that the “ OFF” mark
can face the upper position. (Fig. 5)
(2) Set 1R371 and fasten it counterclockwise by Impact driver
with 19mm Hex socket bit for approx. 2 seconds. (Fig. 4)

19 mm Hex
socket bit

Fig. 5

Repair

[3] DISASSEMBLY/ASSEMBLY
[3] -3. Clutch Drum

DISASSEMBLING

(1) Separate Gear case from Engine section. (Figs. 1, 2 and 3)
(2) Remove Gear case cover from Gear case.
(3) Disassemble Clutch drum. (Figs. 6 and 7)

Fig. 6

Lock Spur gear 9 with 1R374 for disassembling
Clutch drum located on the reverse side of Spur gear 9.

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Note:
Hex socket head bolts removed from
Gear case cover can be used for
fixing1R374.

Fig. 7

Gear case

Gear case
(reverse side view)

Hex socket head bolts for fastening
Gear case cover to Gear case

Spur gear 9

1R374

Fix 1R373 to these holes and
remove Clutch drum by turning
1R373 clockwise.

Clutch drum

13 mm Hex
socket bit

1R373

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Repair

[3] DISASSEMBLY/ASSEMBLY
[3] -3. Clutch Drum (cont.)

ASSEMBLING

(1) Lock Spur gear 9 with 1R374. (Fig. 6)
(2) Drive Clutch drum to the shaft of Spur gear 9 counterclockwise by hand.
(3) Mount 1R373 to Clutch drum and fasten it counterclockwise with impact driver and 13 mm Hex socket bit. (Fig. 7)
Note 1: Do not lose Friction plate next to Rod when mounting Clutch drum.
Note 2: Replace Gear case gasket to the new one.

[3] -4. Spur Gear 9

DISASSEMBLING

Remove Spur gear 9. (Fig. 8)

Fig. 8

1. Apply 1R024 to Shaft of
Spur gear 9 and press it
with Arbor press.

1R024

Gear case

ASSEMBLING

Assemble Spur gear 9. (Fig. 9)

Fig. 9

Put Gear housing on the turn base of Arbor press horizontally.
Insert Spur gear 9 into Ball bearing in Gear case and press it with Arbor press.

Shaft of
Spur gear 9

2. Now, Spur gear 9 is disassembled.

Spur gear 9

Gear case complete

Repair

[3] DISASSEMBLY/ASSEMBLY
[3] -5. Shear Blade

DISASSEMBLING

Remove Holder and Shear blade assembly by unscrewing two Hex socket head bolts. (Fig. 10)

Note: 2 pcs. of Sleeve 5 are mounted under Plate. Do not lose them. (Fig. 12)

Fig. 10

Spur gear 43

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Holder

Gear case

ASSEMBLING

(1) Align the Shear blade (upper) with the lower one. (Fig. 11)
(2) Set 2 pcs. of Sleeve 5 under Plate of Shear blade assembly. (Fig. 12)
(3) Set the position of Spur gear 43 as drawn in Fig. 13.

Fig. 11

Seal

Hex socket head bolt

Note:
Holder and Washer are fastened with Hex socket

Washer

Fig. 12

head bolts. Do not lose them when removing
Shear blade assembly.

Plate

Fig. 13

Shear blades

Sleeve 5

Shear blades

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Repair

[3] DISASSEMBLY/ASSEMBLY
[3] -5. Shear Blade (cont.)

ASSEMBLING

(4) Mount Shear blade assembly in the Gear case while fitting Shear blade’ boss into the hole of Connecting rod.
Fix the Shear blade assembly to Gear case by driving Hex socket head bolt through the Holder and
each Sleeve 5.
Note: • Do not forget to mount Seal. (Fig. 14)

• Apply Makita grease N. No.2 to the portion designated with black triangle. (Fig. 15)

Fig. 14

Spur gear 43

SealHolder

Boss

Gear case

ADJUSTMENT

(1) Loosen Hex lock nut.
(2) After tightening Hex socket button head bolt, turn it back by 1/4 to 3/8 counterclockwise.
(3) Tighten Hex lock nut fully while locking Hex socket button head bolt with Hex wrench. (Fig. 16)

Fig. 16

Lock Hex socket button
head bolt.

Fig. 15

Connecting rod

Cam portion

Apply the both of Cam portions
which accept Connecting rods.

Connecting rod

Tighten Hex lock nut.

(4) Check the clearance by inserting 1R366 into the gaps of all Hex socket button head bolts. (Fig. 17)

Fig. 17

• If 0.4 gauge can be inserted, the clearance is too big.
It causes poor cutting performance.

• If 0.2 gauge can not be inserted, the clearance is too tight.
It causes over consumption of fuel due to high friction load
and heavy load on gears.