Kawasaki SA340-A1, SA440-A1 Quick Reference Manual

"'-

,

Quick Reference Guide

SECTION

Specifications .........................................................................

Maintenance

and Theory

..................................................

Repair .......................................................................

Appendix .....................................................

...

.....................

...

.................

....

.......

...

.................

...........

................. .

....

............... .

...

..

........

.

Using locating a desired topic or shop

manual.

sired section above

the

of contents procedure

the

table

for

quick

Bend

of

contents

the

required

reference

the

with

exact page(s)

.

guide procedure

pages back

the

black

for

that

will

assist

contained within

until

you

tab

on

the

section. Refer

to

locate

the

you

match

right

to

the

specific

QUICK

in

quickly

this

the

hand

side table topic

REFERENCE

de-

of or

GUIDE

ii

,).',Jf~

"

SPECIFICATIONS

Table of Contents

General Specifications .... .

Service Specifications

Torque

Gear Ratio Engine Port

Chart . .

Chart .

Performance Curves

Dimensions

............

........

.......

......

.

...

.......

.........

...

......

.......

.

...

....

.

........

.

.. ..

.....

.

........

.....

......

. . . .

.

...

. . .

.......

...

......

. . . . 1-2

.. ..

.. .. ..

1-4 1-5 1-9

1-10

1-11

/

TABLE OF

CONTENTS

1-1

GENERAL

SPECIFICATIONS

MOD

GENERAL

Overall Length . Overall Width Overall Height (No Windshield) Dry

Weight

ENGINE

Models

Displacement

Bore x Stroke . .

Number Engine Engine

Starter . . . .

IGNITION

Ignition

Spark Plug

.........

of RPM RPM

System . . ....

...

. .... .... . .

...

..... ..

(Ap

proximate)

. .

...

..

. . . . .

......

..

. . . . .

Cylinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

at Full

Throttle .............

at Idle

Speed

...

. .

...

..

.......

......

....

.....

ELS

. . .

...............................

.....

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

......

................

......

. . .... . .

.....

SA340-A1

......

.

....

. ............

. . .... .

..

...........

......

..................

.... . . .

...

..

. .

......

... .......

AND

......

. . .

.....

..

.....................

...

....... ......

..

...

. .

......

..........

. . ..........

................

.....

.. ........

.......

...........

.

.....

...

...........

.

...

. . . . . . .... . .

. (SA340-A 1) 2.362 x 2.362 inches (60 x 60 mm)

(SA440-A

(SA340-A 1) 6,500

.

...

. . . . . ..

SA440-A1

. .

102

inches (2.590 mm)

.....

.

..

......

..... . 35-1 /2 inches (902 mm)

. .....

...

.....

28

inches (711 mm)

.........

..

Type Type

(SA340-A

(SA440-A

1) 2.677 x 2.362 inches (68 x 60 mm)

RPM

...

.....

..

.............

....

...

.....

355 pounds (161 kg)

340T

A,

used

on

SA340-A

440T

A,

used

on

SA440

1)

20.7 C.I. (339cc)

1)

26.6 C.I . (436 cc)

(SA440

.

.......

. Magneto - Breaker Point

. . .

-A 1) 6,800 . .

2,000

Manual rewind

...

NGK

1

-A 1

RPM RPM

BR-SES

CARBURETOR

........

...

.......

....

......

...

....

..

...

. . . ....

...

...........

...

.. ..

....

......

..... . .... . .

...

.....

.

......

......... . . . . .

.. ......

....

. .... . . .

......

.......

.....

.......

.....

.

.....

....

..

...........

....

. . . . .

. . . . . . . . .

. . . . . .....

Carburetor Make Carburetor Model . . Setting No. . Type

of Carburetor ... . . . .

Main Jet . . . . .

Air

Jet . . .

Jet

Needle Needle Jet . Thrott

le

Slide

Pilot

Jet . .... .... .

Pass

By Pilot Air Screw

Float Starter Jet . Type Starter System

FUEL

Gasoline

Oil . . ....

Gasoline/Oil Ratio .... ....

Fuel Tank Capacity .....

....

Outlet ...

Valve Seat .

of

Float Chamber . . .

.......

. . .

.... ....

.. ..

...

.......

. . .

.

....

.. ..

........

...... ..

.....

...

. ..............

. . .

...

....

. . .

....

. . .

.....

.

........

..

......

...

.....

......

. ....

.... ....

.

........................

..

.

........

.......

.... ....

.

........

. . . . . . .

... .......

....

.....

..

. . . . .

....... ...

..............

........

.......

....

...

. .

.

......

. ..........

. .... . . .

...

(25

to

...

.....

....

. . . .

......

.

.......

.....

. .

......

. . ....... ......

.

..........

.........

......

...

........

......

1) 1 quart

...

. ............

..

.....

.

....

. .

......

..

...

..

. . .

. ;

......

...

. .

. . Regular leaded

.........

..........

. . . .

....

............

......

.........

..

.....

......

.. ...........

(0.94 liters)

...

......

..

........

..

. .

. . . .

. . . . .

......

..

....

..

. . . .

MODEL

SA340-A 1

.....

.. ..

...

....

. . .

. .

Mikuni Mikuni VM 34

.

...

.

...

. . . . Open

.....

. 260 . . . None None . . .

.....

. . . . . . 1.4 Dia.

...

. . . 1.5 Dia. 1.5 Dia.

...

(minimum

.. ..... ..

of

oil

....

6DH3-3 6DH4-3 . . 2.5 2.5

25 25

. 0.8 Dia. 0.8 Dia.

. . 1.5 Turns 1.5 Turns

. . 2.0 Dia. 2.5 Dia.

. Standard Standard . Cable Cable

pump

to

6.25 gallons (23 .6 liters) . .

...

Zinc

VM 34-130

Vent

P-6

posted octane number 89)

... B.I.A. certified T.C.W.

.. 6.25

gallons (23.6 liters)

SA440

-A 1

VM

34

Zinc VM34-131 Open

Vent

310

P-6

1A

Dia.

of

gasoline

1-2 GENERAL SPECIFICATIONS

DRIVE

CONVERTER

SA340-A1

MODEL

SA440-A1

Engagement Speed (approximate rpm) Maximum Spring Part Spring Spring Spring Spring Length - New wi Number Number Spring Wire Diameter . Spring Rate (standard) Spring Rate (optional) Spring Compression @ 1.25 Inches (standard) . Spring compression @ 1.2 5 Inches (optional) Weight Part Weight Color (standard) Weight Markings (standard) .

Weight Thickness . . . .

Weight -

Ramp Part

DRIVEN

Cam Spring Spring Spring Length - New Sp

ring Diameter ... .

Spring Wire Diameter Spring

Drive Converter rpm

Number

Part Number Color Color

of Spring Coils (standard) of

Spring Coi

(standard)

(optional) (standard) (optional)

th

no load* . · . . ·

ls

(optional)

· . · .

·

· .

Number

(standard)

. .

Total

gram weight

Number

Pa

rt

Number

050845 050803 050777 050778 050779 050776 050836

CONVERTER

Angle .

Part

Color . . . . . .

Preload - Counterclockwise

.....

Number ...

(standard) .

· . · .

.

... ...

. . ....

...

. . .

with

no load . .... .

......

..

.......

· .

·

.....

. .

. . . · .

.

· .

. .

· . .

.

. . .

· .

· . · .

· .

..

...

....

..

.......

..

· . . .

· .

Black Gre Whit Yellow

Black Red Red

. ....... . .

. .

....

...

. .

........

...........

...

. .

·

· .

..

· ...

. . .

· .

. .

·

...

· .

· . · .

...

.

·

. . .

. .

..

. . .

. . . .

· . · .

· . . · . .

. .

· .

· . · ..

· .

·

..

· .

·

· . .

· .

Color

.. ..

.............

..

....

. . . .

Optional Weights

en

e

.......

. .

..........

. .....

.....

· . . .

·

..

·

...

· . .

·

..

· .

· . · .

· .

·

..

· . .

·

..

.

· .. · . · .

.

....

..

·

· . .

· . . · . . ·

·

...

· . .

· .

..

· . · .

· .

.

· .

. . .

· .

·

.. . .

.......

.

.......

.

..............

.....

· . · .

· .

· . .

· ..

· .

. . . .... . .

....

.....

. . . . .... . . .

. ....

· .

· . · .

· .

·

...

. .

...

· .

..

· .

..

·

..

· . · ..

· .

Markings

0146-279 0146

-136

0146

-107 0146-123 0146

-135 0146-106

0146-286

. .

...

.

..

.

. .

..

.

...

. .

3500 6500 050760 050786 Yellow Green

4.35±0.187

5.35

5.0

0.187

inch 45-53Ibs 60-66 I bs

145·1651bs 192-212Ibs 050835 Black 0146-278

0.250

6.475 050851 050851

30

050774

Black

4.60

2.

0.156

2nd

inch

0

inches

880

inches

hole - 1/3

/in. /i n.

.

turn

3500

6800 050760 050786 Yellow Green

4.

35

± 0.187

5.35

5.0

0.187 inch 45-53 Ibs/in.

60-66 Ibs

165Ibs.

145-

192-212Ibs.

050836

Red

0146-286

0.250

8.800

Gram Weight

5.457

9.279

4.958

6.992

4.479

5.958

8.

800

0

30

050774

Black

inches

4.60

2.880 inches

0.156

2nd

hole -

/in.

inch

inches

1/3

turn

BELT

Part

Number Outs ide Circumference . Width -Top Thickness Belt

Taper Angle .

BRAKE

M

inimu

GEARING

Top

Sprocket Lower Sprocket Cha

in - Doub

Drive Chain Tension (free movement)

*

After approx lo

ss

surface

Top

of

belt

m Brake

Sprocket . .

of

spring compression

.........

Overall

le

imate

Pad

Ratio

row

35

ly

to

bottom

Thick

ness

. . .

.....

.......

....

. .

50 miles, the spring

. .

..

. .

.......

will

occur because

of

lug

........

...

..

.......

. .... .

....

..........

will

..

. .

........ ...

.

.....

........ .... .

.....

. . . .

take a

of

..........

....

.......

. . .

........

"set"

and lose 0.25 (1/4)

the decreased spring length.

.

..

. . . . .

....

..

...

05065504

43. 5 ± 0.25 inches 1-1

/4 ± 1/32 inches

..

. .

.

. .

.

0.56 ± 0.03

0

30

1/16 inch

18 teeth

37 teeth

2.05

90

pitch

3/8

to

of

an

inch

to

1

1/2 inch

of

inch

its

total

length.

GENERAL SPECIFICATIONS

05065504

43.5

± 0.25 inches

1/32

1-1/4 ±

0.56 ± 0.03 inch

0

30

1/16inch

19 teeth 36 teeth

1.87

to

90

pitch

3/8

to

No

inches

1

1/2

inch

significant

1-3

TRACK

Track Track Track L Susp

AND SUSPENSION ..

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Molded rubber

Width

en

sion

........

eng

th ...

........

...............

.

............

.......

.

..........

. .

... ...

....... .. ..

. . . . .... . .

...

.......

.

.. .........

...

..

. . . .

....

.....

........

...

..

. . . . . . 15 inches (381

. .........

. . .

......

with

116

inches (2,946 mm)

..

.....

. Slide rail

steel bars

mm)

ELECTRI

Type Headlight T

Instru

FRA ME

Frame . . . . .

E

NGINE

Effectiv Piston Ring Side Play (Top Ring)

Piston Ring Side Play (

Piston Ring End G

Pi

Conne c

Connecting Rod

Crankshaft End

Crankshaft R un O

CAL COMPONENTS

........

.........

ail/

Brake

Light

ment

Lights . .

e Compression Ratio

ston Ski

rt Clearance

ting

Rod Radial Play

.

..........

.

..................

.......

..

.. ..

ap .....

Small End Diameter ... .

Play

ut

..

....................

........

Bot

tom

. . . .

.

.........

................ ...

.

.........

. .....

....

SERVICE

..........

....

Ring)

..

.......

....

. .... . . . .... . . .

.....

.

...

.......

....

. . .

......

..

. . . .

....

..........

..

. .

...

. .....

....................

................

..

........

.....

...... ........

.....

. . . .

....

..

... ...

..

. .

............ .... . . . G.E. No. 1035

.

....

. . . . . . .

.....

Aluminum

SPECIFICATIONS

SA340-A1

. ....

..

.

6.6:1

.

..........

. . . . .

..

. . .

......

.........

....

......

. . .

_ . . . . .

. . . . . .

. .

...

....

.

..

.

0.004-0.006 in. (0.102-0.152 mm)

. .

0.002-0.004 in. (0.051 -0.102 mm) .006-0.0 14 in. (0.152-0.

0.0008-0.0022 in. (0.

020

. . .

0.0008-0. (0.020-0.

.

0.7875-0.7880 in. (20.003-20.015 mm)

0-0.030 in.

(0.0-0.762 mm)

0.0012

(0.

030

356

-0.056 mm) 0012

030

in.

mm) (max)

. . . .

...

....

...

alloy and steel

MODEL

mm)

in.

mm)

. . 12 volts - 100

. .... Stanley

.. _ ...

. . G.

construction

SA440-A1

6.6

:1

0.004-0.006 in.

0.102-0.152 mm)

0.002 -0.004 in. (0.051-0.102 mm)

0.008-0.016 (0.020-0.406

0.0008-0.0022 in. (0.020-0.056

0.0008-0.0012 in.

(0.020

-0.

030

0.7875-0.7880 in.

(20.0030-0 . (0.0-0.762 mm)

0.0012

(0.030

20.015

030

in.

mm) (max)

E.

in.

mm)

watt

A5988

No. 57

mm)

s

IG

NITION

Spark Plug Gap

Ignition

t Remove spark plug

Timing

NOTE: conditions

1-4 SERVICE SPE

..............

.......

Item L

Lighting Coil Yell ow-Br Exciter

Primary tSecondary

Defective coils cannot always be detected

Coil

Item

caps

is

the recommended test

.

.....

....

..... .

method

CIFICATIONS

....

.

....

.....

. . . . . . .

Red

or White-Grou nd

Ignitio

Red

or white to ground

High tension

usi

.

. . . . . . . 0.020-0.

(0.5-0.6 mm)

..

250 or 0.139 i

Magneto

eads

own

n Coil

Lea

ds

l

ead

to

ground

ng this test alone.

024

in.

n.

Use

of

a coil tester which simulates operating

0.020

-0.

024

(0.5-0.6 mm)

250 or 0.139 in.

Resistance

0.18 Ohm ± 10% Ohm

1.13

1.

61

5165

± 10%

Resistance

Ohm

± 10%

Ohm ± 10%

in.

CARBURETOR

Air

Screw Setting

Idle Screw Setting ...

CHASSIS

Converter Offs et Distance . .......

Converter Ce Drive

Chain Tension (free movement) . . .

Brake Lever Movement ......

Track Tension . . . .

Steering Tie Rod

Alignment

Adjusting Stud ......

......

nter

Distance ......

...

.......

. .

.....

. . .

...

. ....

...

.. ..

. . .... . . . . . .

. . .

.. ..

. .

...........

............

.. .......

......

... ................

.......

..

. .

.....

. . . .... . .

. . .

...

. . . . . . . . . .

.. ..

..

. .

...

. . . .... . . . . .

. . . ....

. . .....

. .... . . . .

...

. . . .

.....

...

.........

...

....

. .

......

. . . . .

...

. .

.. .. ..

SA340

1.5

turns off seat

3

turn

s open

bound

initial

R.P.M.

final)

..

.....

....

..

...

.... 3/8 to 1/2 inch (9.5

........

.. 3/4

inch maximum

...

. . ....... 1-

M

ODEL

-A l

1.5 tu

from

(2,

000

.

.......

.....

.

.......

. . . . . Skis parallel

3 turns open

coil

bound

R.P

0.454 inches (11.5

... :.

10.3 inch

. . . .

defle c

tion

114

inch (32 mm) maximum

40-A

SA4

rns

off seat

ini

tial (2,000

.M.

fin

al)

es (262 mm) to

3/4

inch (19

(5 to 8 Ibs pu

or

1/8

from

12.7

inch t

l

coil

mm)

mm) mm)

ll)

oe

in

GENERAL

Cylinder Head Bolts ... ....

Crankcase Flywheel Recoil Spark Plug

ENGINE

Bolts and Nuts ... . . . .......

Nut

Bolt

... ...

TORQUE SPECIFICATIONS

. . .

...

......

...

..

. . . . .

. .......

TORQUE

ENGINE

Engine Muffl

Engine mo

E

LECTRICAL

Volta Brak e and Volta Tail lamp lens

ead

H He

MOUNT & EXHAUST

rubber mo

er m

ounting

unti

ng screws

SYSTEM

ge

regulator

throttle

ge

regulator

mounting

lamp housing

adla

mp

rim

mounting

unt

nuts

mounting

lever lock screw

mounting

scre

mounting screws

scr

.. .. ........

. . .

.......

........

...

....

.....

CHART

Descri

ption

nut

screw (grounded

ws

ew 1 50 in. Ibs. (0.5 8 kg-m)

.

...

. . .

......

...

. .....

. . . . ....

to

chassis)

..

....

...

. . .

. .

...

.....

.. .......

AND

. . . . .... . ....

......

. . .......

......

. . .... .

...

..

....

...

....

. .

. . .

.....

....

. 16 ft/

......

...

........ 60

...

. . . . .

.........

. . .

LOC-TITE TABLE

Quantit y

30

4 4 10 ft . 4

1 1 25 1 95 in . 2 50 in. Ibs. (0.058 kg-m) 4

ft. Ibs.

30

ft

. Ibs. (4.1 5 kg-m)

95

in. Ibs. (1.09 kg-m)

ft.

11 ft. Ibs. (1.52 kg-m)

Torque

(4.15 kg-m)

Ibs. (1.38 kg-m)

Ibs

. (3.46 kg-m)

Ib

s. (1.09 kg-m)

...

lb

16

ft/lb

.. 5 ft/lb

20

ft/lb

(2.213 kg-m) (2 .213 kg-m)

(8.3 kg-m) (0.7 kg-m)

(2.7 kg-m)

Loc-

Tite

DRIVE

Spider Spider assy Sp

,.

Ramp

Movable s

Drive converter assembly to cran

CONVERTER

assy

ider

assy

mounting

hea

. - roll er bear

. set scre

. -

set

ve

to bearing housin g

ing

mountin

ws

screw nuts 3

screws 3

ksh

g nuts

mountin

aft bo

g socket scre

lt

ws

3 3

3

1

35-48 in. Ibs. 35-48 in.

35-48 in. 24-30 in. 15-17 55-60

Ibs. (OAO-0.55 kg-ml Ib Ib

ft.

Ibs.

ft. Ibs.

SERVICE

(0040

-0.55 kg-ml

s.

(0.40-0.55 kg-

s. (0.28

-0. (2.07 -2.35 kg(7.61-8.30 kg-m)

35 kg-

ml ml ml

SPECIFICATIONS

1-5

\

Oescri?tion

10ROUE CHARI

~CON1\NU

\

EO)

Quantit'!

\

"\

ot(\ue

\

\..oc-lite

~

DRIVEN

Disc brake Mounting Nut Nut -mounting screw - clevis retainer Nut

CHAIN

Chain Chain Top Chain Cap Top Bearing Tensioner stopper

Jam nuts - chain

Bottom

Tensioner stopper

SUSPENS

Rear suspension bracket Mounting Rear axle

Axle Mounting Mounting Nut Nuts Attaching Attach

Wear

Cross shaft Mounting Mounting Mounting

CONVERTER & BRAKE

to stationary

screw - clevis retainer

- securing

- caliper

case

sprocket

case

- speedometer drive adapter sprocket bearing retainer ring

bracket

- shock absorber

- eye

ing nuts -

strip

front

to

mounting

CASE

mounting cover

mounting

cover plugs 2 20 in. Ibs. (0 .23 kg-m)

support

sprocket

assy

case

ION

screws - washer

support

mountin

screws -

nut -idler

bolts

to

nuts - screws

support

attaching screws

mounting

screws -

screws - suspension brackets -

bolt -idler

sheave

mounting

to

caliper

to

brake

bracket

nuts

screws 2 20 ft. Ibs. (2.77 kg-m)

screw 1 19

to

clevis

mounting

brackets

limiters

shaft

to

suspension brackets

upper

shaft

screw

set screws

nut

mounting

to

limiters

mounting

g screws

to

front

bolt

rear suspension arm

to limiters

brackets

screws

idler

shaft

screw

cam

support

mounting

nuts

suspension arm

to

cam

nut

screws

chassis

front

bracket 2

screws 3

and rear

18

3

95 in. I bs.

1

95

120 in. Ibs. (1.38 kg-m)

1

95

1

4

1

1 1

2

1 1

4 2 8 8 2 1 1

4

2

9 4 2 8

1

19

17 ft. Ibs. (2.35 kg-m)

Hand 95 95 95

17 in. 55 95

17 95 95 95

95

ft.

17

30

ft.

Adjust

95

in. Ibs. (1.09 kg-m)

95

in.

60

in. Ibs. (0.69 kg-m)

30

ft. ft.

15

25

ft_ ft. Ibs. (2.63 kg-m)

19

(1.09 kg-m)

in. Ibs. (1.09 kg-m)

ft. Ibs. (2.63

ft.

Ibs. (2.63 kg-m)

Tighten

in.

Ibs. in. Ibs. (1.09 kg-m) in . lbs. (1.09 kg-m)

Ibs. (0.20 kg-m)

kg

-m)

(1.09 kg-m)

ft. Ibs. (7.61 kg-m)

in. Ibs. (1.09 kg-m)

ft

. Ibs. (2.35 kg-m) in. Ibs. (1.09 kg-m) in. Ibs. (1.09 kg-m) in.

Ibs.

(1.09 kg-m)

in . Ibs. (1.09 kg-m)

Ibs.

(2.35 kg-m)

Ibs.

(4.15 kg-m)

Ibs.

(1.09 kg-m)

Ibs.

(4.15 kg-m)

Ibs.

(2.07 kg-m)

Ibs. (3.46 kg-m)

242

242 242

DRIVE

Bearing housing Bearing housing Nuts

SKI & SPINDLE

Attaching Attaching

Screw Nut

1-6

SHAFT

mounting

grease

- bearing housing

nut

- skeg (ski wear runner)

nuts - spring

sp

indle

to spring saddle

- spindle

to

spring saddle

TORQUE CHART

screws fitting mounting

to ski

screws

to

ski

3 1 3

4 4 2 2

95

in. Ibs. (1.09 kg-m)

40 in.

Ibs. (0.46 kg-m)

95

in. Ibs_ (1.09 kg-m)

ft.

Ibs. (2.07 kg-m)

15 10

ft.

Ibs.

(1.38 kg-m)

40 ft.

Ibs.

(5.53 kg-m)

45

ft.

Ibs.

(6.22 kg-m)

I

TORQUE

CHART

(CONTINUED)

S

TEERING

Nut

- steering column

Nuts·

steering arms Steering Steering Ti Tie Nut Handle bar

CHASSIS

Snow

Hood Hood Attaching Passeng Pan

FUEL

Fuel Air Att

column column

e rod jam

rod jam

· R H tie rod

brace attach ing screws

silencer support

aching nuts · fuel

nut

-

nut·

to

steering column

flap

mounting guide and guide,

front

nuts·

er

handles attaching nuts

SYSTEM

pump

assy

Description

to

tie rod

to

tie rods mounting mounting

nuts, upper

screws, lower

LH

RH

to

steering

front

bumper and hood hinge attaching nuts

rear bumper and snow

mounting

screws

bumper

pump

column

mounting

screws

screw

assy

and air silencer support

screws

flap

Quantity

1 4 2 2 2 2

1 4

4

12 18

8

4

2

1

3

Torque

35

ft.

Ibs. (4.

84

30

ft.

Ib

s.

(4.15 kg·m)

17

ft.

Ibs. (2.35 kg-m)

13

ft.

Ibs. (1.80 kg-m)

35

ft.

Ibs. (4.84 kg-m)

ft.

Ibs. (4.84 kg·m)

35 30

ft.

Ibs. (4.15 kg-m)

95

in. Ibs. (1.09 kg-m)

95

in. Ibs. (1.09 kg-m)

95

in. Ibs. (1.09 kg·m)

95

in.lbs.

(1.09 kg·m)

95

in.lbs

. (1.09 kg·m)

60 in.

Ibs

. (0.69 kg-m)

95

in. Ibs. (1.09 kg·m)

95 in.

Ibs.

(1.09 kg-m) 95 in. Ib 95

s.

(1.09 kg-m)

in.lbs. (1.09 kg-m)

Loc-Tite

kg-m)

242

CABLES

Brake cable jam nuts

cable

Choke Choke

CRANK

Flywh

CRANKCASE & CYLINDER

Cylinder head nuts (long) Cylinder head nuts (short) Spark plug Cylinder head Crankcase Crankcase nuts

INTAKE & EXHAUST

Mounting

Intake I ntake

Exhaust

assy

cable pal

& PISTONS

eel

nut

NGK

bolt

bolt manifold manifold

manifold

nut

BR8ES

bolt

stud

- carburetor holder bolts

(long)

bolts (short)

nuts

12

ft

2

1 1

1

2 16-19-1 /2 6 2 8

1 16 ft. Ibs. (2.21 kg-m)

10

I

2 2 4 4

. Ibs. (1.66 kg-m)

6

ft.

Ib

s.

(0.83 kg-m)

Hand Tighten

60

ft.

Ibs. (8.30 kg-m)

16·19-1/2 ft. Ibs. (2.2-2. 20

ft.

Ibs

. (2.

16-19-1/2

16

ft.

Ibs. (2.21 kg-m)

40 in. Ibs. (0. 4

-5

ft

. Ibs. (0.55-0.69 kg-m)

ft. Ibs.

4-5

10ft.

Ibs. (1.38 kg-m)

ft.lbs

. (2.2-2.70 kg-m)

70

kg-m)

ft.

Ibs.

(2.2-2.70 kg-m)

62

kg-m)

(0.55-0.69 kq-m)

kg-m)

TOR QUE

CHART

1-7

TORQUE

CHART (CONTINUED

)

FAN

CASE & AI R

Fan assembly Air

shroud

Fan

MAGNETO

Breaker S

tator

Exciting

stator plate

Condenser

ELECTRICAL

Coil bracket

Ignition

RECOIL

Drive plate Sta

rter

Starter

case

contact

plate

coil # 1,

coi l

pulley mounting

mounting

to

STARTER

mounting

SH

ROUD

to

pulley

mounting

screws

crankcase

mounting

stator plate

mounting mounting screws

mounting

exciting

bolts

screw 2

screws

coil

screws

mounting

screws 2 5-6

nut

bolts

Description

nut

s

# 2 and

screw

lighting

coil

to

Quantity

1

11

4 10-12

3 5-6

4 2

4 5-6

1 3 5-6 ft. 3

Torque

30

ft.

Ibs.

(4.5 kg-m)

Use

impact

driver

ft.

Ibs. (1.4-1.7 kg-m)

Use

imp

act

driver

ft.

Ibs. (0.69-0.83 kg-m)

Use Use

impact impact

ft.

driver driver

Ibs. (0.69-0.83 kg-m)

ft. Ibs. (0.69-0.83 kg-m)

ft. Ibs. (1.11 -1.38 kg-m)

8-10

Ibs.

(0.69-0.83 kg -m)

5-6

ft.

Ibs.

(0.69-0.83 kg-m)

Loc-Tite

222

NOTE: required. required, the the specif ied consumer

Loc-Tite formulas are selected on the

Generally,

or

torque

equivalent which may

#222

the fastener diameter

necessary

formula

to

is

remove a fastener.

on each fastener requiring Loc -

basis

used

on fasteners

is

greater than 5/16 inch (8

Be

careful when applying

be

substituted

is

Loc-

up

of

to 5/1

Tit

e " Lock 'n

the diameter

6 inch (8

mm),

:#

242

extra

e. Loc-Tite #

Sea

of

the fastener, and the strength

mm)

diameter.

is

specified. Loc-Tite may

force

as

222

and

l,"

product

If

a particu

this

risks damaging the parts.

:#

242

are

industrial designations. The

number 21, blue.

of

larly

strong

significantly

the bond

bond increase

Use

only

is

1-8

TORQUE CHART

G')

m

~

-4

o

C')

J:

~

-4

...

cD

,

GEAR

RATIO

CHART

DR

IVE

SPROCKET - NUMBER

OF

TEETH

15

16

17

18

19

2.00 : 1 Gear Ratio

34

*62 MPH

88 Chain Pitch

:r:

I-

UJ UJ

2.33

:1

2.19: 1

I-

Gear Ratio

LL

0

0:

35

*53

MPH

*

57

MPH

UJ

co :2:

88 Chain Pit

ch

88 Chain Pitch

::>

z

I-

UJ

2.40:1

1.90:

1

~

u

Gear Ratio

0

0:

0...

36

*52

MPH

*65

MPH

(/)

z

UJ

>

88

Chain Pitch

90

Ch

ain

Pitch

0:

0

2.18: 1

2.06: 1

Gea

r Ratio

Ge

ar

Ratio

37

*57

MPH

*60

MPH

90 Chain Pitch 90 Chain Pitch

-

*Theoretical

MPH

@ 6500

RPM

NOTE: A ll

top

speeds

based

on 1: 1 clutch ratio and engine

RPM

at 6500 .

20

21

1.6

2:

1

Gear

Ratio

*77

MPH

90

Chain Pit

ch

1.75: 1 Gear Ratio

*

71

MPH

90 Chain Pitch

.

- -

--

ENGINE PERFORMAN

340 ASTRO

45

40

CE

CURVES

C/l

0

I

a:

L.U

5:

0

a..

L.U

a:

35

30

25

20

15

10

5

f'./

~

a a a.

M ..r

a a a

a. a.

..,--

/

V

F

/

UEL

CON

a

I.!)

ENGINE

440 ASTRO

HORSEPOWER

YN

/

SUMPTION

TORQUE

-

a a a.

<0

RPM

..............

-

a a a

a

I.!).

a.

<0

r--

a

I.!).

r--

60

40

20

1.60

1.40

1.20

1.00

0.80

C/l

CIJ

-1

f-

---

u..

L.U

=>

d

a:

o

f-

a:

I

r::i...

I

C/l

---

CIJ

-1

L.U

=>

u..

a:

L.U

5:

0

a..

L.U

C/l

a:

0

I

45

40

35

30

25

20

15

10

5

r--..

/X-....

a

o

q

M

/

.---r

/

,I

~EL

.......

a a

o.

..r

/

TORQUE

I'

CONSUMPTION

--

a

o

q

I.!)

ENGINE

RPM

HORSEPOWER

I---

/

r\

--..

'"

-"

a a a a a a

0.

<0

L!l.

<0

0 0

O.

r-- r--

L!l.

60

40

20

1.60

1.40

1.20

1.00

0.80

C/l

CIJ

-1

f-

---

u..

L.U

=>

d

a:

o

f-

a:

I

a..

I

C/l

---

CIJ

-1

L.U

::::>

u..

....

1-10

ENGINE

PERFORMANCE

CURVES

t

B

PORT

DIMENSIONS

MODEL

=

A

B

=

C

=

D =

E

=

F

=

G =

H =

I = 1.93 in. (48.9 mm)

J

=

SA340-Al

1.42 in. (36

1.48 in. (37.5 mm)

0.93 in. (23.5

1.61 in.

1.16 in. (29.5

3.76 i

0.56 in. (14.1 mm)

1.93 i

0.56 in. (14.1 mm)

(41

n.

(95.5 mm)

n.

(48.9 mm)

mm)

c

t

Ht

F

MO

DEL

SA440-A 1

1.57 in. (40

A =

1.52 in (38.5 mm)

B

=

0.93 in. (23.5 mm)

C =

1.81

D =

1.16 in. (29.5

E

=

3.76 in. (95.5

F

=

0.56 in. (14.1

G =

1.93 in. (48.9

H

=

1.93 in. (48.9

I

=

0.56 in. (14.1

J

=

in.

(46

mm)

mm) mm) mm) mm) mm) mm)

PORT

DIMENSIONS

1-11

1-

MAI

NTENA NCE

MAINTENANCE

LUBRICATION

THEORY

Two-Stroke Carburet

Ignition Electrical Torque Torque Driven Chain Case Tra

MAINTENANCE

Two Fuel Ignition Electrical

Converters ....

Drive

Chain Case Track,

STORAGE

OF

OPERATION:

or

System

System ......

Conver

Converter System ..........

Converter .......

and

ck,

Suspens

-Cycle Engine System

System

Converter and Driven Co

Alignment

and

Suspension

.....

Table

CHART

CHART ...

Engine .

.. .. ..

........

ter

Gearing

ion,

. .

...

. . . . . .... . . .

...

..

.......

Gearing ...... .

. .

. . .

..............

.....

. .... .................

and Steering

.....

...........

.......

..

. . .

.......

. . . .

and Steer

.....

Of

Contents

...

......

. .....

............ . . . . .

.

.. .....

.

........

.....

...

......

...........

. .

.....

.. ..

System

...

.....

...........

...

.

...

.....

..

...

nverter

ing System

.

...

. . . . ......

..

. . . . . .

. . .... .......

.. .. ..

....

.... . . . . . ........

. .

......

. .

.. ..... ..

. .... . . . .....

.... . .....

. ......

. .... .... .... . . .

. . . . . . .

...

....

.

......

...

..... . . .

. . . . .

. . . . . .

. . . .

.

......

. . ......

. ....... . .

. .... . .

.....

....

. . . . . . .

.....

...

..

. . .

....

.....

. .

....

. . . .

..

...

....

..... 2-36

Page

2-3 2-4 2-6

..

.

2-6

.

13

2-

.

2-22

..

.

2-

22 2-22 2-

23

.

2-

24

..

.

2-

25

..

.

2-25

. .

2-26 2-

26

. . .

2-

26 2-

27

. .

2-29

.

2-31

2-

32

... 2-35

. .

2-39

TABLE OF

CONTENTS

2-1

Maintenance

Chart

Frequency

Operation Install

plugs Check carb uret

adjustment Check th

adjustme Check

adjustmen Rep De-carbon engine and

exhaust Check breaker

Check i

new

rott nt

enrichener

t

lace

fue

gni

tion ti

spark

or

le cable x

cable x

l f il

ter

points

ming

Beginning

of

Each

Season

x

First

50-100

Miles

5-10

or

Hours

Use

x

x x

x

Every

300

or

Hours

x

Miles

20

Use

Every

600

or

Hours

Miles

40

Use

x

Every

900

or

Ho

Miles

ur

s Use

x

60

End

of

Each

Season

x

Page

Refer-

ence

•

Replace drive belt (be

converter

sure are clean and

dr

Check and al

ignment

Check d rive conver bushings

Clean and drive and converters

Check adj

Adjust track tens ion and check

Check ski align

Adjust

Check fastene rs f

secur chart

ive

dr

iven con

dr

ive chain

ustment

brake

it

y (use t

as a guide)

dry

converter

for

wear

inspect

dr

iven

align

orque

pu lIeys

)

verter

ter

men

ment

or

x

x x

t

x

x x

x

x x

x

Inspect ski for

wea

Measure rail

wear

Adjust headlight

r

wear

str

run

ips

ners

of

slide x

x

MAINTENANCE

CHAR

T

2-3

Lubrication Chart

Lubrication

Point

Lubricant

Frequency

Illustration

CONTROL CABLES Inner

cables

CO

DRIVEN Ramp surfaces

NVERT

sliding

ER

LP

S,

WD-40, Dri-Slide si

milar temperature lu

bricant

L

ow temperature

grease.

or

low

.

Once a season

and every

of

operation.

Once a season and every hours

20

of

operation.

hours

CHAIN CASE

HOUSING

SUSPENSION ARMS,

Rear

Front and

Sno

Jet

Chain

Lubrican

Low temperature E.P. (Extreme Pressure ) Grease .

t.

Check level every

20

hours

Once a season and every

hours

of

40

of

operation .

opera

tion.

2-4

LUBRICATION CHART

LUBRICATION CHART (CONTINUED)

lubrication

STEER COLUMN

FRO BEARING

ING

NT AXLE

Point

Lubricant

Low

temperature

E.P

. Grease .

Apply 3 pumps

of

grease

nd-

operated

ha grease gun. CAUTION:

The seal may be

dislodged by grease, check afte r greasing be

aring .

with

the

Frequency

Once a season and every hours.

Once each season.

a

40

Illustration

.....

LUBRICATION

CHART

2-5

Theory the

I

ntrod

All

by a are: 1. Intake, 2. and

A compressed,

A

comp

Each following the the

1. Intake: On

2. Compression :

Two-Stroke

uction

internal

four

4. Exhaust.

fuellair

two-stroke

lish

of

the

engine

charge engine

stroke, starts fue

II air

volume.

of

combustion

part

cycle

mixture

burned, and

engine

all

four

parts

path

(Figure 2-1

the

of

fuel

through

the

intake

back up. This

m ixtu re

Operation for

Engine

engines

of

operation. The

Compression,

must

be

exhausted

uses

parts.

can be eas ily

of

the

fuellair

).

downstroke

mixed

Near

with

an open

the

port

is closed,

upstroke

to a fraction

drawn

only

air

port

bottom

are

characterized

3.

Combust

into

the

.

two

strokes

understood

mixture

of

the

is

drawn into

in

the

of

the

and

compresses

of its

four

the

parts

ion,

engine,

to

ac-

by

through

piston

the

cylinder.

down-

piston

the

former

3.

Combustion: presse

d,.

down

. This is called

4. Exhaust: rises aga in, through cycle is ready

The piston is power the

The intake most air

into the the

a

effectively drawing pi presses 55°-60° upper ind mixtu through

stroke

crankshaft

complex

have been

the

crankcase.

cyli

nder

lower

ston

blocks

the

BBDC (before

edge of

er

wall re

in these

in

that

When

it

is ign ited

After

pushing

the

now

to

carried

to

the

.

of a two

part

mixed

wall (the

edge

of

increases

the

mixture.

the

mixture

the

piston

are

conn

the

crankcase,

transfer

the

mixture and

forces

the

power

the

power

open

start

through

-stroke

of

the

in

the

As

the pi

intake

the piston. The

the

volume

intake

in

the

bottom

uncovers

ected ports

stroke,

the

burned

exhaust

again.

each

the

rot

engine

cycle.

After

carburetor, it

ston

port)

On its

port

and lightly

crankcase. At

dead center),

to

the

under

into

has been

the

stro

ke.

the

gases

port.

and

step

from

ating

inertia

is

perhaps

the

fuel

is

drawn

rises, a

is

uncovered

of

the

return

ports

crankcase. The

pressure,

the cylin

hole

rising piston

crankcase,

trip,

in

the

rush

er.

com-

piston

out the

one

of

the

and

in

by

the

com-

about

the

cyl-

es

2-6

THEORY

OF

OPERATION

Figure 2-1

o

There are the

crankcase , and two-stroke is called fer

or used because inder helps to clean the

combustion engin

After rises, closing

opening

above

TOC

the

two

separate intake actions:

termino

the

int

ake;

scavenging

the

log

the

flow.

new

second

y,

only

into

the

second is called

The

word

mixture

flowing

the

first

intake

"scavenge"

exhaust

chamber.

g"

the

exhaust

the

piston passes

the transfe

the

intak

the

piston is compressed as

This

is

.

BOC

(bottom dead

r and

exhaust

e again. The

known

mixture

the

piston nears

(top dead center), the spark plug is fired and

mixture

starts

burning

.

first

into

cylinder. In

action

the

trans

into

the

cyl-

out

of

the

as

"scav

center

ports, and

rapped

is

) it

-

crankcase. The more time there crankcase.

crankcase

mos

pheric

dir

ection. The 600 ABOC, wo

uld seem

BT

OC, on a piston int

ake to and all

the

mixture

th

e open intake.

just

remain

the

If

th e intake is opened too soon,

pressure

and

which

ideal

after

port

crankcase to the

Transfer

sooner

is

to

will

the

mixture

transfers

is

the

to

open

the

transfer

engine

open

cylinder

the

intake is opened,

draw

the

mixture

be

higher

will

flow

generally

same the

close

as

1200 BTOC. It

intake

at

ports close. However,

this

would

until

1150 ATOC as

pressure

would

meant

be lost back

than

in

the

about

require

to

the

into

the the

at-

wrong

ataround

115

the

well,

transfer

out

0

The piston is

unt

il the edge of the piston. The through the

piston, and

dr

exhaust

all

four

iven

downward

port

is uncovered by

basic parts

one

complete

by

the

two

-stroke engine goes

in

just

two

rotation

crankshaft.

Intake

A

two

-stroke

ca

rbu reto

To

get

the

be an opening

the opening

push

the The intake closes of

The

the same

TOC

fuel/air

and takes a

89°

ABOC 89° BBOC

engine's

r.

mixture into

to

or

mixture

timing

Figure

2-2

mixture

certain

TYPICAL

intake

tract

starts w i

the crankcase, there must

the

carburetor. There is a valve in

the pi ston on its

back

out

through

is "s

ymmetrical,"

number

of

degrees on

downstroke

the

).

in

the

amount

PISTON

intake

VALVE

TOC

of

tract

time

ENGINE

to

combus

the

tion

uppe r

strokes of

of

the

th th

will

carburet

or.

it opens and

either

side

has inertia,

get

into the

76° ATOC

Trans

fer

ports

are

designed to move mixture scavenge the the exhaust port opens before exhaust direction. As exhaust trans

e

such a inder, haust

The size and shape portant small, port of the flow scavenging. Recent port s

till

c

arefully enter of the

Timing BB ca haust mix less

symmetrical transfer open too long,

into

from

the

crankcase to

exhaust

gases are already

the

pressure in

will

no

longer

fer

ports

aim

the

way

that

it

will

pushing

the

port.

for

efficient

the

transfer

is too large,

inertia

of

after

s can be made

the

it

the

gases

leaves

almost

get good scavenging

controlling

the

cylinder

the crankcase

lower

the crankcase pressure.

of

the

OC to

nnot

about

open

would

the

new

power

. The

volume.

transfer

600 ABOC. The

until

after

flow

into

charge and the

(or

none

about

port is

important

some

the crankcase.

the

from

the

traveling

the

cylinder

flow

of

its

incoming

sweep

exhaust

of

the

fuel/air

throughout

gases

transfer

scavenging.

flow

will

be restricted.

flow

speed

will

affect

the

port,

studies

indicate

as large as possible

at

low

the

angle

transfer

at port

The larger

ports

runs

the

exhaust

the

crankcase. This

exhaust

at

all).

Transfer

BOC. The closing

to

good

of

the

mixture

the

fuel/air

cylinder,

and to

cylinder. Because

transfers

own

toward

If

will

drop. The lack

the

resulting

do,

in

the

right

drops,

accord. The

mixture

the

ports

are

they

are too

If

direction

in

that

transfer

the the

in

cyl-

ex-

imthe

of

poor

and

engine

which

speeds by

the

passage is

the

passage,

from

about

transfer

does

or

gases

ports

the

part

60

ex-

would

resulting

port

point

cylinder

will

timing

filling.

flow

of

back

in

is

the

If

0

BOC

Figure

2-2

Compression

closes the

presses the

fr

action

pression mechanically

of

occurs

intake

fuel/air

its

original

any

sealed.

as

the

and

mixture

volume.

kind,

piston

exhaust

in

the

on its upstroke

ports the To

cylinder

and

cylinder

achieve

must

INTAKE

com-

to

com-

be

2-7

a

The

cylinder

from the

tween

the

both compression and

gasket."

standing head gaskets are s a

luminum. Others asbestos sheet to

the

cylinder, squeez ing

ju

st the

head, in

cylinder

head

itself. The

and

This gasket high

temperatures

are a

s.

The head must be

right

amount

most

the

cylinder

combustion

must

imply

a sh

sandwich

of

force to

engines,

be capable and

the

leaking.

fit

in

circle

the cylind

rings

es

up

or

two

the

ton

the

or

must

and

compression sealing

The pi ston is a close

the final seal is made by pis

steel alloy rings and

pr

ess

outward

vent

leakag e

the

piston. The piston temperature while

inder

Mo

st

rubbing

wall.

engines

whi

of

compression

s and

constantly

have one

ch

against

pressur

piston rings. Their job is to seal

the

piston and cylinder.

These rings are them

wear ) onger. Plain

but

wear

more

seal

sooner

mu

st be

conform

inder

initial

The cross-sec

exactly wall, wear

when

"broken

but they is the brea

tion

sometimes

quickly

they

in."

to

tiny

of

a ring is an

chrome

iron

rin

and

for

are new. N

The n

irr

egulariti es

gradually wear

k-in

period.

its design. Ring s having a sec tion type has a

This type

it

s groove has ring outward

bus should sometimes should ma

are

called

of

ring has parallel

wedg

e-shaped cross-section (see Figure 2-3).

of

ring is called a

non-parallel

and its groove

aga

inst

tion stroke for

not

be

also have a

always

nufactu

be

rer' s instructions

"flat"

are

the

cylinder

better

installed

install

rings. The groove

walls.

Another

"key-ston

walls.

designed to

wall

sealing. Key-stone ring s

upside

"top"

ed

carefully

.

is separate

joining

surface

is sealed

by

the

of

pressures

eet

of

copper or

of

copper a

fastened

head gasket

keep

cylinder

bore,

rings. These are

piston

er

in

wall

grooves

combustion

withstand

with

out

deforming

down

the

on the cyl-

gap

between

plated to make

gs seal j

thi

ew

rectan

s reason

ew

piston rings

rings

to

imp

ortant

gu l

ust

of

the

fit. This

ar

type

e"

rin

The shape

for

ce

the

during

down.

and

the

Flat

"bottom"

following the

be-

against

"head

with

. Some

nd

tightly

with

it

from

but

to pre-

past

high

as well

they

do

not

cyl-

part

of

cross-

for

thi

of

ring

g and of

the

ring

com ring

s

and

-

Th

e compress ion di fferent from BDC to TDC displ

acement

wo-s

troke engines are

t second method. engine displ

acement

s

FLAT

RINGS

ways

in Fi

KEYSTONE

RINGS

Figure 2-3

rat

io

may

be

. The

above

ent

may

the

ire cyli

be used, exhaust generally

As

an

example

gure

2-4

with a 60

can be figured as sh

"

DYKES

RIN G

measured

nder

displacement

or just

port. Kawasak

rated by

, imagine the

mm stroke. Its

own.

in

,

"

two

the

i

the

third

type

of

A

This ring is

piston . so the

inder cylinder

It

is placed

that

one

edge slightly. The

wall

combustion

of

the

upper leg

cylinder

2-8

wall

COMPRESSION

ring is

usually

side

of

during

twisting the ring

stroke the gas

of

for

a good seal.

the

"Dykes"

used alone on a s

at

the

upper

"L"

ring

shape

is

forced

edge

protrudes

again st

the upstroke by the drag

outward.

pressure

the

"L"

forces

it

out

patt

ern ring.

ingle-rin

of

the

piston,

above

the

cyl-

of

the

During

the

on the in side

against

the

g

BORE = 60 mm ST ROKE = 60 m m

Fi

gure

2-4

2

V

=n-r

WHERE:

=

displacement

V

r =

112

= stro

h

7r

=

3.1416

V

(3.1416)

V

169.6

If

the

engine has a

ume

of

can be

h

bore = 30

ke = 60

(3) (6)

cc

or

20

cc

at

figured

.

volume

mm

or

3 cm

mm

or

6 em

approximately

total

combustion

TDC,

then

the

170

cc

chamber

vol-

compression ratio

The compression ratio sure

of

the

efficiency compression ratio, will

use its

with

a high

horsepower

of

gas

lower

The

further burned, more

heat

fuel, for

than

an

compression ratio.

the

hotter

will more expansion that fuel

means

used and

more

the

up to a

compression

its size

otherwise

mixture

the

be produced.

of

the

horsepower

the

engine

of

an

of

more

and

the

engine

certain

ratio

go

identical

engine

efficiently

further

point.

will

is one

. The

put

on a

engine

higher

the

An

out

is compressed before It

combustion

will

Greater

for

the

be and

heat

products, and

amount

size.

mea-

the engine engine

more

gallon

with

IS

the

means

of

a

R

WHERE:

R - compression

V -

displacement

V -

volume

at

170 + 20

R

20

R 9.5

This is called

However,

cyli

nder

of

at

SDC, the

look I ike

V =7I"r2h

at

the

if

the

we

se.

the

compression

WHERE:

=

displacement

V

= 112 bore =

r

= distance

h

top

of

exhaust

from

71"=3.1416

(3.141 6) (3)2 (4)

V V 113.1 cc

or

ratio

volume -170

TDC -

20

"theoretical"

measure

closing

of

volume

30

mm

or

top

of

port = 40

about

113

cc

compression ratio.

the

total

the

exhaust port

ratio

above

3 em

cylinder

mm

cc

volume

calculations

exhaust

port

to

or

4 em

of

the

instead

might

Combustion

Combustion is trodes of a

The spark plug receives a

voltage instant. wi

power

ign ite 6000 for so TDC

When

that

mixture

front"

flame

burning Normal

electricity

If

II

try

to

stroke the revolutions

this

lead is

that

peak

at

high

the

is

ignites

travels

front

combustion

the

across the speed. There are several types bustions common

metallic,

hard, flame the

front

mixture

an even

related to the

started

spark

by a spark across

plug

in

the

timed

to

ignite

the

ignition

run

backward; too late and part

will

m ixtu re at

to

cylinder

comes too soon

be lost. The

17°

before top dead

per

minute

start

the

mixture

pressures

speeds.

spark plug fires,

between

moves

mixture

its electrodes . That

the

mixture

across

the

across

as

is a

combustion

it

around

combustion

the

it

goes.

single

chamber

and all are undesirable. The

is

detonation. Detonation

hammering

travels

resulting

burning

octane

almost

of

from

instantaneously

in

an explosion

the

mixture.

of

the

gasoline used.

the

elec-

combustion

mixture

ignition

surge

at

the is

chamber.

of

high-

the

right

engine

of

the

timed

center

and up). The reason

burning

will

occur

ignites

the

in

just

mixture

time

after

burning

it,

and a "flame

chamber. The

combustion

flame

at

of

chamber,

front

traveling

just

the

abnormal

right

com-

most

sounds

the

engine

like a

. The

through

rather

than

Detonation

to

(at

is

V

+ V

1

R

2

V2

113 + 20

R

20

R = 6.7

This is

ratio, and is a

usually

called

Iways

the

"corrected"

lower

compression ratio.

than

compression

the

theoretical

"octane"

The

defines

that standard set the octane ,

detonation.

of a gasoline

gasoline's

of

laboratory

the

more

Octane

ratings

resistant

to a laboratory procedure ability two

produce gasoline to

adding petroleum

makes

detonation

to

resist

petroleum

detonation

distillate

meet

tetra-ethyl

of

distillates. The "lead"

it

burn

more

.

lead

is a

burning

conditions

speed

the

number

. The

gasoline

which

under

higher

are assigned according

which

to

that

fuels.

octane

or

certain

slowly,

compares a

of a mixture Oil

companies

requirements

high-octane

in

the

gasoline

thus

avoiding

fuel's

COMBUSTION

a

is to

of

by

2-9

When

molectJles carbon-dioxide, pounds, and heat. Heat is absorbed by the and combustion products. Heat absorbed by engine bustion them the

The shape a chambe r more resista induce tion per

Smoothly designed . having a squish area: bustion top squirt chamber with the sphere . be a smoothly with allows chamber"

lowest.

the

mixture

place. The

actual

factor

resistant; and

unit

of

molecules

of

is

wasted,

products

to expand. This expansion is

power

of

in its

with

mixture

of

volume

surfaced

Mixture

chamber

the

piston (at TDC), causing

out

from

roof

the

lowe

An

a squ ish area

a

smooth

espec ially

burns, a

of fuel

the

air

to

water,

but

incr

eases

in

the

engine's

ability

nt

as

st

to

few

projections

to

detonation.

turbulence

chambers

detonate

combustion

turbulence

roof

between

the

piston nears TDC. The shape

surface area per

ideal

finished,

around

scavenging

chemical

combine

produce carbon-monoxide,

traces

heat

that

combustion

when

of

that

their

engine

combustion

resist

detonation. A smooth

are more

with

less

that

is a

comes

the

aimost

the

scavenging

reaction takes

with

oxygen

other

various

engin

goes

into

the

pressure,

what

.

and

irregulariti

Chambers

highly

less surface area

than

chambers

can be induced by

part

very

the

piston and

unit

chamb

spherical

edge . This design

flow

forcing

produces

chamber

detona-

others.

are easily

of

the

close

to

mixtur

of

volume

er

would

chamber,

across the

flow

com-

the

com-

is

es is

that

com-

the

e to

the

is

shou

Id

be placed near the cent

so

the

flam

e f ront w ill have

to

travel to reach all

plug is on one edge

e

front

has to travel all center, the far.

of

Part min

ed by the top bottom piston is strengthen c

enter

and

ra

As

the

connecting around its circle, cylinder piston's inder durin

g compression. The set, in the crankpin travel of

the

in

der

wall

the crankpin does, and piston

of

combustion

flame

the

combustion

of

the

generally

its

center

to take up space in

ise

the

compression ratio.

piston is forced

rod increases . The

and

then

being

wall

piston's

thrust

during

direction

near

. The piston reaches TDC

is

points

of

the chamber, the

the

front

only

chamber

of

the

piston. It becomes

chamber

away

back again.

combustion,

sideways

minimized

at

shaped

. Some

the

downward,

from

against

piston

opposite

TDC. This lessens

motion

er

of

the

shortest

of

the

chamber

way

across . From

has to travel

shape is

TDC. The top

in a gentle

pistons

combustion

the

one

"slap"

(Fi9ure

have a ra ised

the

crankpin

centerl

This

results

side

and

the

hole

is

the

against

slightly

at

2-5)

angularity

ine

of

other

slightly

direction

the

the instant

.

chamber

distance

. If

the

flame

the

half

as

deter-

the

of

the

arc

to

chamber

of

moves

of

the

in

the

cyl-

side

off-

of

impact

the

cyl-

before

Compression high

compression ratio

to

avoid

use a

The compression is a more accurate detonation pression bustion rising piston. ratio may

Another ignition. hot

on

may flame the flame

ignition will

lead to serious

Another design is spark plug placement. The spark plug

lower

or

a fleck

the

be

front

plug fires, its

front

soon overheat.

ratio

is

important

detonation. A low

octane

than

pressure

chamber, before

An

leak, causing

type

If

the

head

of

ignited

traveling with

creates advanced

consideration

gasoline.

pressure

measure

its

is

the

engine

of

abnormal

combustion

of

carbon

the

piston heats up,

before

engine

the

across

flame

a small,

Detonation

to

combustion.

requires a high

compression

produced by an

of its resistance

compression ratio. Com-

pressure

ignition,

with a high

low

compression

combustion

chamber

on the

front

damage.

chamber

plug

the

meets

sharp

timing,

and

in

combustion

fires. This

octane fuel

engine

in

the

produced by

compression

pressure.

is pre-

becomes very

surface

the

mixtur

starts

chamber.

the

sound

and

preignition

When preignition . The pre-

the

engine

chamber

can

to

com-

the

or

can

A

--

...... ~ ...

_----OFFSET

e a

Figure 2-5

2-10

COMBUSTION

The piston

drical shape only

when

when the engine

pand evenly

through

and are thicker save expand more The

wall

greater to handle motion across the piston with

an expands cylinde

cannot

or

the

engine

as

it

the hea

for

extra strength;

weight.

of

r.

The

than

thi

ckness

the

pi ston. The piston

elliptic

al shape.

into a cylindrical

be made in a perfectly

the

piston

was

heats up. Near

d (Figure 2-6), the piston

upper

the

near

the str

would

was

cold, and

hot. A piston does

part

skirt, and

the

esses

bosses and

As

the

fit the

the

skirt

of

the

must

piston pin holes is

of

the

will

must

piston

shape and

cylin-

cylinder

not

fit

well

not

ex-

ring grooves

walls

is

thin

to

pis

ton

will

be smaller.

reciprocating expand

heat

more

be made

s up,

it

fits the

exhaust ri g piston through

The exhaust haust exhaust excessive noise .

port.

ht

direction. After

for

ces

the

exhaust

system cons

port

manifold,

gases

This

forces

the

re st

through

and a

quickly

Engine Design

Theory, of the

under

the

engine are

low

stood.

function,

er

end

and

important, but

the

bottom

of

port.

ists of

the

muffler

and

design

(crankca

gases

dead center,

the

cylinder

easily

se)

to

move

burned

a passage

head, an ex-

. It removes the

while

of

the

upper

not

complete

function

in

the

ri s

gases

from

reducing

portion

until

s

the ing out

the

are

The

rather makes

when Usually across the about 3/1 edge. The inder gauge in measured taper.

it

check ing

the piston is measured

diameter

(if

two

directions at

Figure

odd shape

important

skirt 6 inches other

. This is measured

available)

not

only

to

piston

at

900 to

(5

half

of

at

four

each position. The

for

PISTON SHAPE

(EXAGGERATED)

2-6

of

the

piston when cold

know

mm)

piston clearance is

size,

where

to

cylinder

with a micrometer

the

piston

up

from the bottom

with a dial-bore

different

but

position s, and

for

roundnes

to

clearances.

measure

bosses,

the

cylinder

s and

cyl-

is

The crankcase supports the use ball

These two of

race, and the wh balls

The crankcase is designed cranks crankshaft,

The crankcase

mating match

rather

Kawasaki

seals

(Figure 2-7).

bearings

ball

bearings

hardened steel races separated by a caged set

steel balls. The

the

crank

turns,

ich roll on

from

rubbing

haft

. In

the

surfaces

perfectly. A sealing

than

two-stroke

and

cylinder

contains

main

bearings.

for

the

are very strong and consi st

crankshaft

crankcase

the

inner

the

outer

against

order

crankcase is sp

must

a gasket,

to

be

of

the

to

engines. The

base baskets have

the

crankshaft, and

Snowmobile

main

bearings.

is

fitted

to

carries race. The cage keeps the

install

airtight

crankcase

the

outer

race rolls on

each other.

to

totally lit

compound

insure

enclose

and remove the

horizontally

and

oiltight.

halv

airtightness on

crankshaft

to

engines

the

inn

race.

the

es

must

is used,

be

airtight

of

er

As

balls

the

.

The

oil

Exhaust

Th

e design major The speed range he

ight useful exhaust BBDC. The he

The

higher

angle. The

last

into

the

effect

of

the

pow

er range

port

bit

exhaust

of

the exhaust

on

the

characteristics

of

the

engine

exhaust

opens and closes

ight

of

the exha

of

pressure

system

port. Proportionately,

of

the

port

ust

port,

in

system and

engine

determines

the

with

timing

of

the

increases

decreases. The

at

about

wider

cylinder

the

800 to

the

is released

opening

engine.

with

its

timing.

exhaust

of

has a

the the

90

the

0

Figure

2-7

EXHAUST

2-11

To achieve good crankcase compression, wheels pletely the space inside the crankcase.

The

parts. A caged crankpin. The

the

the sideways each side

The misaligned pressed together. The perfectly

There is a specified side and radial clearance the

are designed

as possible.

connecting

crankshaft

crankpin needles roll connecting

, and

held

of

the big end.

crankshaft

because

aligned on

big end bearing (Figure 2-9).

to

fill

the

crankcase as

Between

rod. There is

is pressed

needle bearing is used on

rolls

on

the

rod. The

by

two

can

twist

it

consists

the

together

on

inside

of

connecting

thrust

or

loosen and become

of

crankwheels

crankpin (Figure 2-8).

very

the

washers,

the

crank-

crankwheels

little

wasted

from

separate

needles, and

large end

rod is located

one

separate pieces

must

com-

the

of

on

be

for

is

Lubrication

The

lubricating carried gasoline and oil used as a engines. The by the

gasoline, and

Depending upon dations, the ratio can vary some may be even higher).

Some

cated by a variable

mixtu

depending on When gets less

entirely

British

from

snowmobile

re

from

the

engine

oi

I.

oil

for

most

in

the

fuel. Petroil is a mixture

term

"petroii"

from

the

"oil."

the

manufacturer's recommen

of

gasoline

16

to

1, all

engines

pump about engine

18

speed and

needs less oil, as

snowmobile

fuel

in these

was

two

words "petro

to

oil

the

way

are

automatic

which

to 1

to

engines

two-stroke

prob

ably

termed

l"

for

in

a petroil

to

50

may

change

about

throttle opening

at

an idl

to

ally l

50

mix

1 (and

ubri-

the

to

e,

is

of

-

1,

.

it

@)

RIGHT

WRONG

CONNECTIN'G ROD

(BIG END)

THRUST

WASHERS

A+B+C+D = SIDE

RIGHTW

WRONG

Figure

E =

Figure

2-8

CLEARANCE

RADIAL

2-9

CRANKPIN

CLEARANCE

I

Under Automatic engine down

full

throttle, oiling is

only

as

on visible

the

economical

much

exhaust

engine

oil as

emissions.

it

needs. Thi s also

Cooling

All

snowmobile

heat is produced by bustion extra and

The piston is coming flowing

by usually inder overheating.

The by overheating is piston seizure. the against piston onto treme side because clearances and cause seizure. A

loss

can be cleaned, and more damage new

cylinder

gouges

products can absorb

heat

cylinder

from

across

contact

hotter

head, and is

most

common

overheated

the

until

the

cylinder

heat. A piston

of

power.

severe seizure

from

piston and

must

on

engines

combustion

is absorbed by

head.

cooled by

the

bottom,

the

top

during

with

the

cylinder

than

the

first

form

piston cylinder it

begins

that

be

the

wall.

to

melt

wall

will

side

runs

uneven

If

a severe seizure

honing

mild

the

may

cylinder

seizure

damage

the

rebored

walls.

A severe seizure can

need

in

the

piston,

the

new

by

the

walls.

cylinder

component

of

engine

expanding

Friction

. Pieces are rubbed

and

welded

seize

hotter. Inc

cylinder

lock

the

bore.

to

clean

will

be fed

because

to

be cooled.

than

hor

fuel/air

the

scavenging, and

walls or

damage caused

This

adds h

fir

st

on

expansion can also

feels

is

slight,

bore honed. A

engine solid. The

requir

Someti

up

more

it

gives

cuts

More

the

comsepower cylinder

new

The piston is

damaged by

is caused by

and pressing

there

orrect

lik

es

scratches

. This walls

mixture

the

cyl-

eat

to

by ex-

the

exhaust

piston

e a sudden

the

piston

fitting mes

and

dam-

oil.

the

,

the

off

a

the

2-12

LUBRICATION

..

•

age

the

connect

ponents

The water. cooled the exposed heat system become clogged engine

shou

cylinder

At present Kawasaki is developing models. An

cylinder and head

to

given up. If

may overheat.

ing

ld

always

and head

air. The

rod and cranksha ft. These

air

more

the

be

examined

may

be cooled by

cooled

which

cooling

with

engine

increase

area exposed,

fins

foreign

for

damage.

has

fins

the

or

fan

material,

com-

air

or

water

on

area

more

intake

the

VENTURIMEASU

REMENT

1

I I

engine

The fan

blows

heads and

engine

and

most overheat tended period

The average

percentage

Aluminum

minum identica

bare

aluminum wear quickly. chrome others the

iron lin

m inu m

Small

minum will Fau

lty

of

uneven

aluminum cylinder

Carbure

Introduction

The mixing for

efficient combustion

carbureto

A

common

the bore

snowmobiles. The

the

smallest part

The carburetor is the

movement

chooses

I

machine

control from a virtual that

the e

w

ithin its

is cooled by

coo ling

draws

will

not

sno

if

they

of

conducts

cylind

I

iron

plate

have a

er

of

the cylinder

bubbles

insulate

cylinder

heat

of

r.

method

or

venturi

the

at

the

rider

ngine operating

the

air

flowing

air

across

the

heat

be cooled as effectively at an idle,

wmobile

are

allowed

of

time

.

sno

wmobile

lightweight

heat

er

or

head

one. The

because

Some

lining

cast-in

must

between

castings

transfer

cylinder

they

alum

to

make

iron

be in

the

liner, create problems because

from

fins.

the

out

of

the

engines

to

idle

engine

aluminum

very quickly.

will

inum

liner

over

the

contains a high

run

walls

would

cylinders have a

them

wear

. To cool properly,

contact

its

iron

creating

the

iron

over it. A

cylinders and

engine

will

gradually

for

an ex-

components.

An

cooler

be too soft and

entire

than

cannot

acceptably;

with

the

surface.

and

the

a hot-spot.

liner

tor

fuel

and air

measurement

of

the

of

his

engine

desired rate.

can choose a speed

crawl

will

in is the

for

referring

size. This the

venturi

rider's

machine

speed

to

flat

out. The rider expects

respond

range.

the

amounts

function

to

carburetors

method

is

the

(Figure 2-10).

primary

. The

that

will

With

a squeeze

instantly,

required

of

is used

diameter

control

carburetor

propel

anywhere anywhere

. The

alu-

alualu-

to

the

over

of

an

be

the

is in of

the the

The

carburetor

in

the

form which slide, aided by

and jets, regulates engine. When of engine

the

mitted

and power.

The

mixture

The

changing needs ditions of

each 15

"th

a

Due to

speeds or the

richer.

Within burned and economy entering factor tage bustion,

molecule that tained by the availab le

surrounding molecules given mum

uncovers

fuel/air

, causing

slide is

to

carburetor

which

fuel/air

of

fuel

to

eoretical"

fraction

actual

the

in the engine, a balance

for

of

the

all

of

quantity burning

receives

of a pull

numerous

the

mixture

lowered,

the

engine,

reaches

ratio

load and speed. The ideal

air

is

about

grams

mixing

of

the

incomplete

additional

operational

acceptable

must

the

engine

maximum

limited

it

is necessary to

with

enough

the

air

gaining

air. Maximum

.. each

of

air

of

efficiency

Figure

the

slide is lifted, a

flows

it

to

controls

must

of

the

of

time

be reached.

amount

is utilized.

maximum

molecule

to

fuel.

2-10

the

message

on

a cable. This

air

passage

ports, passages, needles,

flow

under

produce

less

fuel/air

causing

the

be adjusted

engine

1 :15

or

air.

This

ratio, and is

that

the vaporization fuel

required

fuel/air

for

combustion

performance.

of

fuel

Maximum

insure

maximum

Maximum

of

the

~

from

to

the

of

fuel

and

greater

the

slide

more

power.

mixture

it

to

reduce speed

amount

engine

air

burning

economy

of

(Figure 2-11).

for

particular

burning

one

gram

is an

only

engine

of

at

ratio

ratios

between

The

amount

is

To

available

surround

molecules

fuel

with

economy

available fuel.

the

rider

lifts a slide

engine. This

air

into

the

quantity

into

the

When

is ad-

of

fuel/air

to

meet

the conratio

of

fuel

"ideal"

achieved

is

fuel

high

is

that

the

take advan-

for

each

to power efficiency is gained by

use

or

for

running.

at

low

speeds,

usually

can be

power

of

air

limiting

com-

air

insure

is ob -

several

from

is

maxi-

to

of

a

CARBURETOR

2-13

these droplets would

~

..

::::::::::::

••

•.

IAiRFLO~

.. . . .

............

~

.

.•.

...•

...

a very rich will

When and air

incomplete atom ization mixture

acceleration,

developed, The greater economy drops rapidly

ridden ing speeds,

stantial,

results in a

in a

be

burned

warmed

flow

actual

for

at

but

of

warm

the

fu

engine. It is necessary

mixture

.

up,

through

idle is rich,

when

mixture

amounts

high

power

II

th rottle

air

flow

the

fuel

slightly

fuel

will

to

insure

the

engine

the

maximum

ratio

of

operation.

much

through

is

lean

not

vaporize as

that

speed

carburetor

of

the

fuel

about

fuel

when

metered

mixture

1:10.

might

and

a

of

the

carburetor

power

.

to

some

of

the

at

idle is

is so

low

occurs. The

Under

is being

be

around 1 :1

air

are much

This

is

why

snowmobile

time.

At

sparingly.

they

provide

fuel

low, that

hard

2.

fuel

is

cruis-

is sub-

This

Somewhere mum

economy is

ually

ridden. The range engine from (Figure 2-12). of broken up

FUEL/AIR

RATIOS

an

air

through

LEAN

1

~

RICH

receives

extremely

into

1: 1:

1: 1 0 1 :8 1 :6 1

:4

between

where

at

At

very

the

carburetor

small

18 16

14 12

./'

U).

Y'~

Figure 2-11

maximum

most of

fuel/air

one

time

rich

1:6

slow

engine

is

droplets

. If

/

/"

"6

<'«'

""

~

(;'

Figure

2-12

power

snowmobiles

or

to

a very lean 1

slow

the

L

r"..

and maxi-

ratios

another speeds

and

the

engine

"'I

"

q,

~

it

fo

are us-

that

the

ranges

:17

the

flow

fuel

is

is cold,

""~

~

<'<,

0""

""

~

carburetor

The

fuel

and air

somewhere to the engine and

rider's

in

load.

Theory

Carburetor operation is based on

ciples when a fluid and (known

pressure as 2-13).

of

fluid

encounters

as a

undergo

VELOCITY

an

LOW CONSTRUCTION

must

have

for

extremes

in

between.

needs by

the

exact

&

Operation

dynamics

(such as air) is

venturi

incr

ease

it

passes

I~IGH

supplying

quantities

an area

or

in

through

VENTURI

VELOCIT~I

the

ability

of

power

The

carburetor

demanded

. These

constriction), velocity and a decrea se

principles

flowing

of

the

UJ::=:qC

HIGH LOW PRESSURE

PRESSURE

Air

is

drawn engine. This the

large

section,

point

in

then

the past a time

(one second).

the

point

soon be a severe

carburetor. To

with the

same

point

in

air

entry

no loss.

entry

in

the

achieve

Figure

in

from

flows

section and

of

amount

the

venturi

If

venturi

pressure

the

through

If

1000

the

carburetor

of

only

in

one

the

2-13

air

the the cc

air

(1000

in

the

900

cc

::Iecond,

build-up same

to

meter

or

economy

fuel

and

the

basic

state

through a tub

smaller

the

venturi

LOW

VELOCITY

: 6

HIGH

PRESSURE

sil

encer

carburetor,

smaller

of

air

flow

in

one

cc)

must

same

amount

could

there

in

front

flow

volume,

the

and

responds

air

to

the

by speed

prin

that

e

diam

eter

fluid

will

in

(Figure

into

the

both

venturi

past a

second,

flow

of

flow past

would

of

the

-

2

-14

CARBURETOR

a

ir

how the tube

flow

must

much constric . The

.

flow

faster

tion

smaller

faster

through

depends on

or

venturi

the

is

venturi,

the

how

than

the

venturi

much

the

rest

faster

. Exactly

smaller

of

the

air

cross-sectiona l area

The

A2 = 3.14 x 13

A2=3.14x169

of

the

venturi

is:

2

41

mm

-,--

-'--

Figure entry The carbur

The

2-14

diameter

venturi

etor

.

velocity

shows a carburetor

of

air) is inversely area of the

the

entry

tube. To

and

equations:

1 =

1T'r

A A2 = 1T'r2

1 2

2

Figure

of

41

mm

dimension

the

air

(or a single

proport

find

the

ventur

2-14

with a maximum

and a

venturi

is

the "size"

"particle"

ional

to

the

cross-sect ional

the

cross-sectional area

i use

the

26m

of

26

of

follow

,-,-

'-

in

m

'-

mm

the

of

ing

A2 = 520.66

The ratio

of

mm

A 1

2

to

13

19.585

A 2 is:

520.66

of

the

The area than

the versely throug than

h the ve

through

Occurring drop in duced

air

pressure carburetor sect

ion.

Under

the

venturi

sure in

the entry

as atmosp

area

proportional

heric

venturi

of

the

entry.

to

nturi

is

the

entry

along

with

pressure

in the

allows

to accelerate

average

will

be

approximately

(which

pressure).

the

conditions,

Metering System

The carburetor consists systems to supply The main system,

mix

fuel

(Figure 2-15).

is

handled

with

supply

air

fuel by a pilot

as

it

2'f3

is

about

Since

the

about

tube

2-112

the

area,

2-112

.

velocity

venturi

air

flowing

through

60%

is

approximately

of a number

and

air

as

fuel

pump

system,

and

is needed by

or

2.53:1 .

time

s less

velocity

is

the velocity

times

greater

increase is a

region.

This

through

the

venturi

the

press

ure

of

the

pres-

the

same

of

separate

required

and

starter

float

the

. Fuel

bowl.

system

engine

in-

re-

the

in

Where: A 1 is

the

area

of

the

entry

A 2 is the area

r1

is the radius (112

r2

is th radius

1T'

is a constant.

express A1 and

larger

the

The cross-sectional area

3.14 x 20.5

3.

14 x 420.25

1319.

entry

585

of

the

of

the

3.14 A2

in a ratio to

is

than

2

mm

2

venturi

the

diameter)

venturi

the

of

find

ventur

i.

the entry is:

the

how

ent

ry

much

The Float Bowl

The float fuel for the The ca

rburetor . The

cavity is vented

inside the

the

Fuel level and a needle valve.The valve seals of

fuel in the

and the needle valve sea

l. fuel bowl, the contact fuel.

the

main

float

bowl.

rides on

against

This a

pump

with

bowl

(or

other

and

pilot

chamber

to

bowl

in

the

bowl

llows

to

flow

floats

rise,

the

valve seat,

THEORY

float systems

systems; and

is

attached

upper

the

atmosphere,

is

the

float

needle

drops,

moves

fuel

pumped

into

the

pushing

AND

chamber) is

which

to

portion

same

bowl

as

is

controlled lower arm,

and

valve seat.

the

floats

down

from

bowl.

the

shutting

OPERATION

the

meter

the

starter

the

bottom

of

the

so

pressure

end

of

the

When

away the

As

fuel

nee

dle

off

air

the

upper

drop

tank

enters

valve

the

source

the

fuel;

system.

of

the

chamber

pressure

outsid

by

floats

needle

end

the

level

slightly,

from

the

by

the the

into

flow

2-15

of

e

of

AIRFl

REDUCED PRESSURE

..

t

FUEL

LEVEL

FLOAT

The

fuel

level

affects

will

run

throughout

this

is

the

drop venturi. phere, so psi) float sure is on the bowl,

which

running,

the atmospheric fuel

acting

level in leased 2-16).

The

low, not

and

starting and lean

too high, too

and

is adjusted by

towards bending

Always

The

float

there

pushing

bowl.

pressure in

of

the feed

float

the

be

into

the

down

When

including

lead into the

the

pressure

in

pressure

the

bowl

on

the

fuel

fuel in

into

able to pull

the

tube

the

level is

decreased

the

air much

engine

the needle valve lowers the fuel level,

it

away

set

the

Figure

how

its

entire

in

pressure

bowl

is a

pressure

on

the

engine

surface

the

is

up

air

would

bending

fuel

of

fuel

venturi.

in

feed

acting

much

in

the

feed

tube

into

the

stream

important

pressure

enough stream. This mixture

fuel

run

frm

the

level

2-15

rich

or

lean

the

range. The reason

that

occurs

is vented to

of

1.03

surface

is stopped,

all

the

inside

When

the

venturi

tubes

on

the

greater

feed tube. Therefore,

ratios. If

is pulled

the

at

than

rises, venturi

as

tiny

at

low

in

the

fuel

up

would

too rich. The

tab. Bending

valve raises

the

kg-cm2

of

the

fuel

this

fuel

in

the

"feed

the

engine

is less, and

is also less. The

surface

the

pressure

pushing

where

droplets

out

the

into

correct

the

it

(Figure

speeds. If too venturi

of

the

cause hard

fuel

level is

the

venturi

float

the

level.

engine

for

in

the

atmos-

(14.7

in

the

pres-

float

tubes"

is

of

the the

fuel

is re-

would

bowl

level

tab

and

level.

Figure

Metering performed by a system has a range is effective,

system takes up and This system to components are tem, illustrates

the

"overlap"

another

pilot

system and

the

fuel

number

but

insures

overlap

and

the

air

of

throttle division another

will

be

throttle

starter

between

the

Throttle Slide

The

amount mined in a closely

the

carburetor body. The controlled by a cable and closed"

the slide the slide is raised through slide is in a venturi, venturi

or

air slide. This is the

most

is used on all Kawasakis.

At

lower

throttle the

cutaway throttle. mixture

higher coming air. The

stant

at

of

air

enter

ing

by

the

throttl

e slide. The

fitting

position,

for

the

and the area

in a venturi. The size

passage changes

common

throttle

slide affects

The

will

cutaway

any

bore

little

the

air

to

venturi

known

is higher

be

and

lower

constant

position,

as a variable

type

positions,

felt

most

at a constant

offers

fuel

supply

directly

or

flow

higher,

into

under

found

mixture

the

less

throttle

2-16

in

the

proper

separate systems. Each

positions between leaves transition

smooth

slid

e,

system . Figure 2-

the

carburetor

throttle

above

movement

spr

ing. In

no space

through

more

the

engine.

it

blocks the of

the

with

the

on

snowmobiles

the ratios.

from

about

cutaway,

throttle

resistance

remains

position, and

amounts

in

which

where

off

is gradua

from

. The

slide becomes a

venturi

cutaway

metering

main

fuel

components.

is

deter-

slide rides

the

venturi

of

the

slid e is

the

"fully

remains

the venturi. As

air

actual

position

The

the

position. The

relatively

will

When

part

venturi

type. It is

effect

1/8

to

leaner to

the

under

of

is

it

one

l.

one

sys-

17

in

flow

the the

the

and

the

of

1/3

the

in-

con-

the

2-16

METERING SYSTEM

Kawasaki SA340-A1, SA440-A1 Quick Reference Manual

Specifications and Main Features

Frequently Asked Questions

User Manual