Shindaiwa HT230 User manual

GEARCASE AND CUTTERS
Shindaiwa HT230 and
DH230 Hedge Trimmers
SERVICE
MANUAL
SHINDAIWA SERVICE MANUAL
DH2301
HT230
DH230
WARNING!
The engine exhaust from this product
contains chemicals known to the State of
California to cause cancer, birth defects
or other reproductive harm.

䊚Shindaiwa Inc. 1998
2
Service Manual
Section page
1Model Identification/Specifications ....... 3
2Internal Gearcase Identification............. 5
3Theory of Operation ................................ 6
4Troubleshooting ...................................... 8
5Powerhead and Cutter Removal .......... 10
6Gearcase Disassembly/Inspection ...... 12
7Gearcase Reassembly .......................... 16
8Cutter Service ........................................ 18
9Cutter and Gearcase Maintenance ...... 23
10 Appendix
Special and Recommended Tools .......... 25
Torque Specifications .............................. 25
Metric Conversions ................................. 26
Contents
CAUTION!
A statement preceded by the word
CAUTION contains information that
should be acted upon to avoid damaging
your machine.
WARNING!
A statement preceded by the triangle
Attention Symbol and the word
WARNING contains information that
should be acted upon to prevent serious
bodily injury.
IMPORTANT!
A statement preceded by the word
IMPORTANT is one that possesses
special significance.
Shindaiwa HT230 and DH230
Hedge Trimmers
Gearcase and Cutters
Attention
Statements

䊚Shindaiwa Inc. 1998 3
HT2301
HT2302
Figure 1. Major Component Identification
Rear Handle
Bracket
Rear Handle and
Throttle Assembly
Powerhead
Gearcase
Air Cleaner
Cover
Hand Guard
and Front
Handle
Assembly
Guide
Bar
Cover
Protector
Cutters
Guide
Plate
Adjustable Shoulder
Bolts with Locking Nuts
DH2301
DH2302
HT230
DH230
Rear Handle and
Throttle Assembly
Powerhead
Air Cleaner
Cover
Hand Guard
and Front
Handle
Assembly
Guide
Bar
Cover
Cutters
Adjustable Shoulder
Bolts with Locking Nuts
Model Identification Section 1

䊚Shindaiwa Inc. 1998
4
Section 1 Specifications
Specifications are subject to change without notice.
General Specifications HT230 & DH230
Dimensions (L x W x H)
HT230-30 ..................... 990 x 210 x 210 mm
HT230-40 ................... 1330 x 210 x 210 mm
DH230-24 .................. 1080 x 250 x 210 mm
DH230-30 .................. 1220 x 250 x 210 mm
Weight; engine and Cutter (less fuel)
HT230-30 .................... 5.5 kg (12.2 pounds)
HT230-40 .................... 6.0 kg (13.2 pounds)
DH230-24 .................. 5.7 kg (12.5 pounds)
DH230-30 ................... 5.9 kg (13.9 pounds)
Engine Specifications
Engine Model ....................................... SHT230
Type ..... 2-cycle, horizontal cylinder, air cooled
Bore x Stroke .......................... 32 mm x 28 mm
Displacement ........................................ 22.5 cc
Dry Weight ...................... 2.6 kg (5.73 pounds)
Max. Output ....... 1.1 hp (0.81 kW) @ 8000 rpm
Fuel ................................. Gasoline-oil Mixture–
40:1 with Shindaiwa
Premium 2-cycle Engine Oil
Fuel Tank Cap., (HT230) ..... 0.7 liter/24 ounces
Fuel Tank Cap., (DH230) .... 0.6 liter/21 ounces
Carburetor ........ Walbro WYJ (diaphragm type)
Ignition ....Fully electronic, transistor controlled
Spark Plug ................................ Champion CJ8
Air Cleaner ................. Semi-wet type, silenced
Starting Method .............................. Recoil type
Drive and Cutters Specifications
HT230 Blade ......... Double-action, single edge
DH230 Blade .......Double-action, double edge
Blade Length
HT230-30 ......................................... 740 mm
HT230-40 ....................................... 1080 mm
DH230-24 ........................................ 605 mm
DH230-30 ........................................ 745 mm
Clutch Type .............Fully automatic centrifugal
clutch, dry type
Gear Type ....................................... Spur gears
Gear Reduction ...................................... 1:4.98
Gear Lubrication ............ Lithium-based grease
Standard Equipment
Rear handle with integral controls, anti-vibe
mountings.
Front handle with guard.
Tool set and blade cover (scabbard).
Options
Deflector shield (HT230 only)

䊚Shindaiwa Inc. 1998 5
Nomenclature
Figure 2. Internal Gearcase Components (shown inverted).
HT2329
Clutch Drum
Grease
Fitting
Upper Guide
Plate
Upper
Connecting
Rod
Sealed
Bearing
Shielded
Bearing
Thrust
Washer
Pinion
Shielded
Bearings
Thrust
Washer
Lower Guide
Plate
Lower
Connecting
Rod
Felt Seal
Gearcase
Cover
Gearcase
Cam
Gear
Internal Gearcase Identification Section 2
Gasket

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Section 3 Theory of Operation
Clutch
Figure 3
Gearcase
Figure 4
Clutch drum rotation is transferred directly to
the input pinion gear, which is in constant
engagement with the cam gear. The pinion-to-
cam gear combination reduces engine rpm by
a ratio of 1:4.98.
Crankshaft rotation is transferred to the
gearcase through a bonded-shoe centrifugal
clutch threaded to the engine crankshaft.
Increasing engine rpm causes the clutch
shoes to swing outward under centrifugal
force, engaging with and turning the clutch
drum on the gearcase.
Figure 3. Clutch Operation.
Figure 4. Reduction Gearing.
HT2337
HT2347
Cam Gear
Retraction
Spring
Clutch Drum
Shoe (swings
outward to engage)
Clutch
Drum
Pinion
Gear
1:4.98
Reduction

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Cutter Drive
Figure 5
Each side of the cam gear is fitted with an
eccentric lobe, and the two eccentrics are
installed 180˚ opposite one another.
Each eccentric is also fitted with a connect-
ing rod mounted on roller bearings, allowing
cam gear rotation to be converted to a
reciprocating action at the opposing or small
end of each connecting rod.
Connecting rod thrust is in turn controlled
by close-tolerances between the cam gear
faces and a set of hardened guide plates that
surround the small ends of the connecting
rods, held between a set of hardened guide
plates.
Via the connecting rods, cam rotation is
converted into reciprocating motion to drive
the cutting attachment.
Cutting
Attachment
Figure 6
The reciprocating end of each connecting rod
is bored to mate with a hardened drive stud at
the inner end of each of the two parallel
cutters, providing true “double action” perfor-
mance.
To allow independent cutter movement, the
individual cutters are slot-mounted over
special shoulder bolts threaded into a station-
ary guide bar attached to the gearcase
assembly.
Cutters are identified as “upper” and
“lower”, and are available with appropriate
length guide bars to provide cutting swaths of
varying widths.
Figure 5. Cam Gear and Connecting Rods
Figure 6. Cutter Drive Operation.
Theory of Operation Section 3
HT2348
HT2349
Eccentric
Lobe
Cam Gear
Lower Guide
Plate
Upper
Guide
Plate
Lower
Connecting
Rod
Upper
Connecting
Rod
Reciprocating
Action
Upper Cutter
Shoulder
Bolt
Guide Bar
(stationary)
Lower Cutter
Slot
Drive Stud
HT230 Shown

䊚Shindaiwa Inc. 1998
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Section 4 Troubleshooting
Performance and durability are highly depen-
dent upon cutter condition, adjustment, and
lubrication.
For a truly “clean” cut, all cutters must be
sharp, undistorted, and in otherwise good
condition.
For consistent cutting action over the length
of the cutter, all shoulder bolts must be in
good condition and properly adjusted to
maintain cutter-to-cutter contact.
Possible Cause
Shoulder bolts too loose
Cutter teeth dull
Shoulder bolts loose
or worn
Worn shoulder bolt slots
Clutch failure
Internal gear failure
Engine idle set too high.
Clutch retraction spring is
broken
Drive stud is broken
Connecting rod failure
Shoulder bolt(s) adjusted
too tight
Internal gearcase damage
Gear or connecting rod
failure
Gearcase too full
Felt seal damaged
Cover gasket damaged
Water in gearcase (possible
outside storage)
IMPORTANT!
Beyond outright abuse, gearcase life and
cutting performance are directly related
to both maintenance and adjustment.
Remedy
Adjust bolts per Section 8
Sharpen teeth per Section 8
Adjust or replace per Section 8
Replace clutch shoe assembly
Overhaul gearcase
Reset idle speed to 3000 ±250 rpm
Replace clutch assembly
Replace cutter per Section 8
Replace connecting rod: inspect for
internal gearcase damage
Readjust per Section 8
Inspect/overhaul gearcase
Inspect/overhaul gearcase
Section 9
Replace seal
Replace gasket
Drain and refill per Section 9
Problem
Poor cutting performance
Cutters not “tracking”
(non-parallel operation)
Cutters not moving, or
move very slowly
(engine revs)
Cutters will not
disengage
One cutter not moving
Cutters/engine revs slow;
engine may overheat
Excessive noise from
gearcase
Grease leaking from
gearcase at guide bar
Gearcase lube has white
“milky” appearance

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HT2301
Figure 7. Common Causes of Cutter or Gearcase Problems
Troubleshooting Section 4
Tip
Damage
Dull or
Damaged
Cutters
Shoulder Bolts
Worn/Incorrectly
Adjusted
Poor
Lubrication
Dirt
Accumulation
Internal Gearcase
Wear
Low or Contaminated
Lubricant
Guide Plate
Worn/Damaged
Worn
Shoulder
Bolt Slots HT230 Shown

䊚Shindaiwa Inc. 1998
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HT2350
Section 5 Powerhead Removal
Powerhead
Removal–HT230
HT2306A
Figure 8. Disconnecting the throttle cable
and ignition wiring
Figure 9. Removing the Gearcase Assembly
and Rear Handle Bracket
Rear
Handle
IMPORTANT!
Service procedures for the HT230 DH230
powerhead are similar to those for the
T230 trimmer and are described in
Shindaiwa Grass Trimmers, Brushcutters
and Lawn Edgers Service Manual
, Form
60506.
CAUTION!
Impact-type power tools can damage the
hedge trimmer drive assembly.
STEP 1. Disconnect the throttle cable end
from the throttle lever on the carburetor
(Figure 8).
STEP 2. Unplug the red ignition wire from the
ignition wire connector, and then tempo-
rarily remove the gearcase mounting bolt
to disconnect the black grounding wire
(Figure 8).
STEP 3. Remove the three 6 mm x 16 mm
gearcase mounting screws, and separate
the gearcase assembly from the
powerhead (Figure 9).
STEP 4. Remove the two 6mm x 35mm rear
handle bracket mounting screws, and lift
the rear handle assembly from the gear-
case (Figure 9).
Powerhead
Gearcase
Assembly
Gearcase
Mounting
Screw
Mounting
Screw
Rear
Handle
Bracket
Handle
Bracket
Mounting
Screw
Red
Ignition
Wire
Black
Ground Wire
Throttle
Lever
Air Cleaner
(removed for
clarity)
Cable End
Handle Bracket
Mounting Screw
Gearcase
Mounting
Screw
Ignition
Wire
Connector
Gearcase
Mounting Bolt