Echo CS-370ES User Manual

CS-370ES01-36E-00

INTRODUCTION

We are constantly working on technical improvement of our products. For this reason, technical data, equipment and design are subject to change without notice. All specifications, illustrations and directions in this SERVICE DATA are based on the latest products information available at the time of publication.

INDEX

CONTENTS

page

1 SERVICE INFORMATION ............................. 2

1-1 Specification ............................................... 2

1-2 Technical data ............................................ 3

1-3 Torque limits ............................................... 4

1-4 Special repairing materials......................... 4

1-5 Service limits .............................................. 5

1-6 Special tools ............................................... 6

2 CARBURETTOR ADJUSTMENT PROCEDURE .

2-1 General adjusting rules .............................. 7

2-2 Presetting idle adjust screw, L mixture needle

and H mixture needle ........................................ 7

2-3 Adjusting carburettor .................................. 9

Reference No. 01-36E-00

ISSUED: 200703

1 SERVICE INFORMATION

1-1 Specifications

Model CS-370ES

Dimensions Length* mm(in) 393 (15.5)

Width mm(in) 245 (9.6)

Height mm(in) 277 (10.9)

Dry weight* kg(lb) 4.6 (10.1)

Engine Type KIORITZ, air-cooled, two-stroke, single cylinder

Rotation Clockwise as viewed from the output end

Displacement cm3(in3) 36.3 (2.22)

Bore mm(in) 38.0 (1.50)

Stroke mm(in) 32.0 (1.26)

Compression ratio 7.6

Carburetor Type Diaphragm horizontal-draught, with auto-return choke**

Model Walbro WT-820A

Venturi size-Throttle bore mm(in) 13.5 - 15.85 (0.532 - 0.624)

Ignition Type Digital Magneto : CDI system

Spark plug BPMR8Y

Starter Type ES (effortless)-start

Rope diameter x length mm(in) 3.0 x 900 (0.14 x 35.4)

Fuel Type Premixed two-stroke fuel

Mixture ratio 50 : 1 (2 %)

Petrol Minimum 89 octane petrol

Two-stroke air cooled engine oil ISO-L-EGD (ISO/CD13738), JASO FC

Tank capacity L (U.S.fl.oz.) 0.41 (13.9)

Clutch Type Centrifugal, 3-shoe slide with 3-tension spring

Guide bar / Saw chain lubrication type Automatic with volume adjuster

Oil Tank capacity L (U.S.fl.oz.) 0.28 (9.5)

Auto oiler Type clutch related type

Sprocket Type Spur

Number of teeth 6

Pitch in 3/8

SERVICE INFORMATION

CS-370ES

* Without guide bar and saw chain. ** Auto-return choke is on switch bracket.

Cutting devices

Guide bar Type 30RC50M-3/8 35RC50M-3/8

Called length cm 30 35

Gauge in 0.050

Saw chain Type OREGON 91VG

Number of drive links 47 53

Pitch in Low profile 3/8

Gauge in 0.050

CS-370ES

1-2 Technical data

Engine

Idling speed r/min 2400 - 2900

Wide open throttle speed* r/min 11500 - 12500

Clutch engagement speed r/min 3800 - 4300

Compression pressure MPa (kgf/cm2) (psi) 1.02 (10.4) (148)

Ignition system

Spark plug gap mm(in) 0.6 - 0.7 (0.024 - 0.028)

Minimum secondary voltage at 1000 r/min kV 15

Secondary coil resistance kΩ 1.5 - 2.2

Pole shoe air gaps mm(in) 0.3 - 0.4 (0.012 - 0.016)

Ignition timing at 3000 r/min °BTDC 10

at 8000 r/min °BTDC 32

at 10,000 r/min °BTDC 34

at 12,500 r/min °BTDC 32

Carburetor

Idle adjust screw initial setting turns in** 1 5/8

L mixture needle initial setting turns back 1 1/4

H mixture needle initial setting turns back 2 3/8

Test Pressure, minimum MPa (kgf/cm2) (psi) 0.05 (0.5) (7.0)

Metering lever height mm(in) 1.65 (0.06) lower than diaphragm seat

Chain oil discharge volume at 7000 r/ min Adjustable : 1.5 - 13 (0.05 - 0.40)

mL/min(U.S.fl.oz./min) (Factory set 7 mL/min)

BTDC: Before top dead center.

* With 35 cm guide bar and saw chain.

** Set idle speed screw to the point that its tip just contacts throttle plate before initial setting.

SERVICE INFORMATION

1-3 Torque limits

Descriptions Size kgf•cm N•m in•lbf

Starter Starter pawl M5 40 - 60 4 - 6 35 - 50 system

Ignition Magneto rotor (Flywheel) M 8 250 - 290 25 - 29 220 - 250 system

Fuel Carburettor M 5 30 - 45 3 - 4.5 26 - 40 system

Clutch Clutch hub LM 10 300 - 400 30 - 40 260 - 350

Engine Crankcase*** M 5* 70 - 110 7 - 11 60 - 95

Muffler M 5 80 - 110 8 - 11 70 - 95

Others Auto-oiler M4 20 - 35 2.5 - 3.5 17 - 30

Regular bolt, nut and screw M 3 6 - 10 0.6 - 1 5 - 9

LM: Left-hand thread *Apply thread locking sealant (See below) ** Tapping screw

Starter case M 5** 25 - 35 2.5 - 3.5 22 - 30

Ignition coil M 5 40 - 60 4 - 6 35 - 50

Ignition switch M 14 15 - 30 1.5 - 3 13 - 26

Spark plug M14 150 - 170 15 - 17 130 - 150

carburetor elbow M 5** 20 - 30 2 - 3 17 - 26

Intake bellows M5 30 - 45 3.0 - 4.5 26 - 40

Engine mount M 5 70 - 110 7 - 11 60 - 95

Cylinder cover M 5 25 - 45 2.5 - 4.5 22 - 40

Front handle M 5** 45 - 65 4.5 - 6.5 40 - 55

Rear handle assembly

Handle lid M 4 10 - 20 1 - 2 9 - 17

Brake lever (Hand guard)

Sprocket guard plate M 4** 10 - 20 1 - 2 9 - 17

Chain catcher M 5 45 - 60 4.5 - 6 40 - 52

Guide bar M 8 200 - 230 20 - 23 175 - 200

SERVICE INFORMATION

M 5 30 - 50 3 - 5 26 - 45

M 4 35 - 50 3.5 - 5 30 - 45

M 5** 10 - 20 1 - 2 9 - 17

M 4** 45 - 65 4.5 - 6.5 40 - 55

M 4 15 - 25 1.5 - 2.5 13 - 22

M 5 25 - 45 2.5 - 4.5 22 - 40

M 6 45 - 75 4.5 - 7.5 40 - 65

CS-370ES

*** The torque differences among four bolts should not exceed 20 kgf•cm (2N•m, 17in•lbf) on crankcase

1-4 Special repairing materials

Material Location Remarks

Adhesive Ball bearing outer / crankcase

Pulse pipe joint

Cushions Loctite #424, ThreeBond #1741 or equivalent

Liquid gasket Crankcase seams Loctite #515 or equivalent

Grease Auto-oiler worm

Clutch needle bearing

Handle cushions Lithium based grease

Rewind spring

Starter center shaft

Chain brake (metal contact part) Molybdenum grease (approx. 1 gram)

Loctite #675 or equivalent

CS-370ES

SERVICE INFORMATION

1-5 Service Limits

ABCD

5K275

5K280

5K277 5K278

5K279

FGH

5K016 5K042

5K276

KLMP

5K173

5K174 5K190

5K191

Description mm (in)

A Cylinder bore When plating is worn and aluminum can be seen

B Piston outer diameter Min. 37. 91 (1.493)

C Piston pin bore Max. 9. 075 (0.3573)

D Piston ring groove Max. 1. 6 (0.063)

E Piston ring side clearance Max. 0. 1 (0.004)

F Piston pin outer diameter Min. 8. 98 (0.3535)

G Piston ring width Min. 1. 45 (0.057)

H Piston ring end gap Max. 0. 5 (0.02)

K Con-rod small end bore Max. 12. 025 (0.4734)

L Crankshaft runout Max. 0. 05 (0.002)

M Sprocket bore Max. 13. 07 (0.5146)

N Clutch drum bore Max. 71. 5 (2.81)

P Sprocket wear limit Max. 0. 5 (0.02)

120

140

160

180

100

1-6 Special tools

SERVICE INFORMATION

CS-370ES

a = 3 mm

a = 4 mm

10 11 1312

14 16

91019

17 

1.65

1.35

0.4

1.5

Key Part Number Description Reference

1 990511-30017 Tachometer PET-1000 Measuring engine speed

2 895612-79920 L-hex wrench (3 mm) Removing and installing hex. socket bolts (M4)

3 895610-79920 L-hex wrench (4 mm) Removing and installing hex. socket bolts (M5)

4 897501-03938 Puller Removing magneto rotor

5 897505-16133 Clutch tool Removing and assembling clutch assembly

6 91007 Compression gauge Measuring cylinder compression

7 897702-30131 Piston pin tool Removing and installing piston pin

8 897701-06030 Bearing wedge Removing and crankshaft ball bearings

9 897563-19830 Metering lever gauge Measuring metering lever height on carburetor

10 897708-19835 Worm puller Removing auto-oiler worm

11 Y089-000010 Worm inserter Installing auto-oiler worm : Crankshaft thread LM8x1.25

12 897726-09130 Oil seal tool Installing oil seals

13 897800-79931 Spark tester Checking ignition system

14 897803-30133 Pressure tester Testing carburettor and crankcase leakage

15 91019 Limiter cap tool Removing and installing limiter cap

16 500-500 Welch plug tool Removing and installing welch plug tool

17 990610-00051 Loctite #515 Applying crankcase seam

18 91004 Module air gap gauge Adjusting pole shoe air gaps

CS-370ES

2 CARBURETTOR ADJUSTMENT PROCEDURE

2-1 General adjusting rules

A. Before starting the unit for adjustment, check the following items.

1. The correct spark plug must be clean and properly gapped.

2. The air filter element must be clean and properly installed.

3. The muffler exhaust port must be clear of carbon.

4. The fuel lines, tank vent and fuel filter are in good condition and clear of debris.

5. The fuel is fresh ( > 89 octane : RON) and properly mixed at 50 : 1 with “ISO L-EGD” or “JASO-FC” 2stroke oil.

6. The recommended bar and chain must be installed, and properly tensioned.

NOTE : In order to achieve proper carburettor adjustment, 30 or 35 cm bar and chain should be installed on the unit. Otherwise serious engine damage will occur due to overspeeding.

B. Set L and H mixture needles full anticlockwise. Start and run engine for two minutes alternating engine speed between WOT for 5 seconds and idle for 5 seconds. Adjust idle speed screw to 2,700 +/- 150 r/min. Adjust H mixture needle to 12,000 +/- 500 r/min. If engine does not run correctly after this adjustment, proceed to the next step 2-2.

SERVICE INFORMATION

IMPORTANT : After adjusting carburettor according to the steps 2-2 and 2-3, the limiter cap(s) must be installed on L and H mixture needle(s) to comply with Emission Directive.

2-2 Presetting idle adjust screw, L mixture needle and H mixture needle

Parts Required : (2) P/N P003-000010 limiter caps.

1. Turn the L and H mixture needles anticlockwise to rich side stop to align limiter cap tab (A) with locating slot (B), using 3 mm blade screwdriver.

NOTE : If cap tabs (A) misalign with locating slots (B), there is a chance to strip thread.

(continued)

2-2 Presetting idle adjust screw, L mixture needle and H mixture needle (continued)

SERVICE INFORMATION

2. Screw threaded end of limiter cap removal tool 91019 with 2.5 mm left-hand thread into center hole of limiter cap anticlockwise until tab of the limiter cap just comes out of the locating slot.

NOTE : DO NOT COMPLETELY REMOVE LIMITER CAP FROM CARBURETTOR! If the limiter cap was pulled out completely, there is a chance that the other mixture needle would turn and limiter cap tab would misalign with locating slot when screwing the limiter cap removal tool into center hole of the limiter cap. As a result, the thread of the limiter cap would be stripped. Use 3 mm diameter thread wood screw to remove the stripped limiter cap.

3. Remove the limiter cap removal tool from the limiter cap by turning the tool clockwise, leaving the limiter cap in place.

CS-370ES

4. Screw threaded end of limiter cap removal tool 91019 into center hole of the other limiter cap anticlockwise until the limiter cap is removed from the mixture needle completely. Remove the limiter cap from limiter cap removal tool turning clockwise, and screw thread of limiter cap removal tool 91019 into center hole of previous limiter cap to pull out completely.

5. Turn L and H mixture needles clockwise until lightly seated, and then turn out both mixture needles following turns.

L mixture needle : 1 1/4, H mixture needle : 2 3/8

NOTE : If needles are forced during seating, damage to carburettor may occur.

6. Remove air filter cover and air filter to see that idle adjust screw contacts the throttle plate. Turn idle adjust screw anticlockwise and set the screw until the tip just contacts the throttle plate. Then turn idle adjust screw 1 5/8 turns clockwise. Reinstall air filter, and air filter cover.

CS-370ES

2-3 Adjusting carburettor

SERVICE INFORMATION

Idle adjust screw

L mixture needle

4. Set idle engine speed to 3,800 r/min by turning idle adjust screw. Engine speed should be stable at 3,800 +/- 50 r/min after idle adjust screw adjustment.

5. Turn L mixture needle anticlockwise reducing engine idle speed 1,200 r/min to set idle speed at 2,600 r/min. The engine idle speed range is 2,500 - 2,800 r/min.

NOTE : Engine speed must be allowed to stabilize a minimum of 20 seconds after each adjustment of L mixture needle to assure accurate tachometer readings.

6. Make sure WOT engine speed is approx. 11,000 r/min. If WOT engine speed is over 11,000 r/min, turn H mixture needle anticlockwise until engine speed drops to approx. 11,000 r/min. Turn H mixture needle 1/8 turn increments clockwise at idle engine speed, then squeeze throttle trigger and check WOT engine speed. If the WOT engine speed is less than 11,500 r/min, turn H mixture needle 1/8 turn clockwise again, and check WOT engine speed. The final WOT engine speed should fall within the11,700 to 12,300 r/min range.

H mixture needle

1. Start engine and warm it up at idle for one minute. Turn H mixture needle anticlockwise until engine speed drops to approx. 11,000 r/min.

2. Warm it up well for 100 sec alternating engine speed between WOT (Wide Open Throttle) for 5 seconds and idle for 5 seconds .

NOTE : Do not run engine at high speed without load longer than 5 seconds, or engine damage may occur.

3. Adjust L mixture needle with 3 mm blade screwdriver to reach maximum engine speed just before lean drop off.

7. After adjusting carburettor, screw new limiter cap on the thread of the limiter cap removal tool 91019 (C) anticlockwise approx. 2 turns as shown, and put the limiter caps on L and H mixture needles respectively. And then press the caps on L and H mixture needles with opposite side of the limiter cap tool (C).

NOTE : Align the limiter cap’s tabs (A) with locating

IMPORTANT : The limiter caps must be installed L and H mixture needles to comply with Emission Directive.

8. Start engine, and verify engine idle speed ranges from 2,400 to 2,900 r/min, and WOT engine speed ranges from 11,500 to 12,500 r/min. Make sure chain does not rotate when engine is idling. When final adjustment is completed, the engine should idle, accelerate smoothly, and attain WOT per above

specification.

NOTE : Initial carburettor setting (idle adjust screw, L and H mixture needles) shown on page 3 and 8 is to start the engine after restoration or carburettor change. Idle adjust screw, L and H mixture needles turn for designated engine revolution through procedures indicated here may vary. As long as idle and WOT engine speed is set in given range, variance would be ignorable.

slots (B) in extended housing of carburettor.

Echo CS-370ES User Manual

Specifications and Main Features

Frequently Asked Questions

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