John deer Jd340/s User manual

~

JOHN DEERE

S,ERVICE TEXTBOOK

for

-

J

~

a

i

Ll

~

N

·

D"·E

·"

:E··DE·

.

::

:,

• .

~

F1

:

(

'::,

-,,,-,:;:

....

:

···

·

·;

M .

. . . . ' . . .

JD340/S

Snowmobile

J'I'

Litho

in

U.S.A. - 1- 4

M65776

. '

-------

-

--

)

CONTENTS

'

-,

"

..

SPECIFICATIONS

••.••..........•..•.

. 2

ENGINE

....•..•.

•

•...........

..

....•

4

FUEL

SYSTEM

••.•••.........•.

•

....••

6

ELECTRICAL

SYSTEM

.•......••.•....•.

12

POWER

TRAIN

•.••••...•..............

19

SUSPENS::IQN

••••••...•.........•..

.

..

26

- 1 -

. ,

,:;,

\

.:'::'..i

~.:

: ,

:.:,

.

:;:

:.

..

.•

:~

.::, , ...' '.

COMPONENT

ENGINE

FUEL

SYSTEM

CHASSIS

AND

BODY

TRACK

AND

SUSPENSION

POWER

TRAIN

ELECTRICAL

SYSTEM

SPEC

IFICATIONS

ITEM

Manufacturer

Model

No.

of Cylinders

Bore

Stroke

Displacement

Horsepower

Ca

rburetor

Mfg.

Carburetor

Model

Tank

Capacity

Fuel

Mixing

Ratin

Ma

't'

eri

'

al:

Tunnel

Hood

and

Pan

Wi

ndshi

e

ld

Overa

la

Length

Ov

,

erall

Width

Overall

Hei

'

ght

We

.i'ght

(1

bs

.

)(

dry)

Suspension

Type

Track:

Manufacturer

Type

Width

Transmission :

Type

Manufacturer

Model

Clutch

Engagement

Engine

Maint.

Speed

Final Drive Ratio:

Standard

Opti

anal

Brake

Dri

ve

Belt

Spark

Plug

Timing

(Dynamic)

Lighting

Coil

Capacity

Light Bulbs:

Headlight

S

op-

Tai

11

i

ght

Speedometer

Tachometer

SPECIFICATIONS

JD/

Ki

oritz

KEC

340

RS/2

2

60

mm

60

rrrn

339 cc

47

@

8000

rpm

M:ikuni

VM

34

(2

used)

9.00

U.S.

gal.

50:

1*

·

Aluminum

ABS

Polycarbonate ,

J04

in.

40

in.

41

i·n.

385

lbs.

Jets

(See

pages

10

& 11)

Slide

(JD295/S

Bogie

Slide w/Gates

Poly Track

Will

Adapt

to JD340jS)

Goodyear

Grouser

Bar

'

15.5

in.

2 Sheave Variable

JD/Come"t

102C

(Primary)

900

(Secondary)

4000

rpm

(Max.)

7800-8200

rpm

2.29:1

2.06~1,

2.19:1, 2.44:1, 2.62:1

Hydraulic

Disk

M65703

Cham~

N-

19V

(AM53l87)

AC

SV4XL

(AM53223)

0.090-inch

(20

0)

BTDC

120

Watt

-

AM52959

(4492)

AM52619

(1035)

AM52847

*With

John

Deere

sn

owmobile

oil

and

Premium

Grade

gasoline.

Use

20:1

ratio

for

f

irst

2 tankfuls.

- 2 -

DETAILED

E

NGINE

SPECI

FICATIONS

NEW

PAKI

WtAR

HEM

DIMENSION

TOLERANCE

·

'.

,:

,.

Cyl

i

nd

er

Bore

2.

3622

to 2.3630 in.• 0.006

in.

Connecting

Rod

A'7~

(Small

End)

0.8664 to 0.8669 i·n.

/'

J.

r1

jf

0.0016 in .

Conne~ting

Rod

Side

Cl

ea

rance 0.000

to

0.002

in.

0.024 in.

~

Crank

shaft

Runout

(Max.)

0.002 in.

Crankshaft

End

Play

(Max

. ) 0.020

in

.

Piston

at

Top

Land

2.3476 to 2.34

84

in.

Pis

ton

at

Skirt

2.3520 to 2.3524

in.

0.005

in.

Pi

ston

Bore

0.7083 to 0.7087 in.

//1117

/11

0.001 in.

Pi

ston

0.7083 to 0.7087 in.; I

'f(

I

./

/1-·,1/

1 0.001 in.

..

Compression

Pressure*

110

to

130

psi

*Check

compression with engine

co

ld

and

throttle

in

wi

de

open

position.

Pressure

should not vary

by

more

, than

1"0

psi

between

cylinders.

ENGI

NE

"

.,

~

..

,. -. .

.

'.

'

The

John Deere/Kiori

tz

340 RS/2 engine

is

basical1:§1

the

~

'

a.:me

a's

other

piston-ported

CCW

engi

nes

in

the

John Deere 1i ne.

Repa

ir procedure'S a'

ret'h:e

same. See

Specifi

ca-

tions

on

pages 2

and

3.

The

high horsepower

level

is

due

to

changes in

port

ti

·

mi

~

ng

.

,

dualcarburetion,

CD

i

gniti

on

and

the

expans ion chamber exhaust system.

IMPORTANT:

Due

to

the

high

output

of

this

engine,

thefO

'I

llowing

precautions

must

be

taken

to

prevent

engine

failure:

1.

Use

only Premium Grade

gasoline.

2.

Mix

gasoline

and

oil

in

a 20 :1

ratio

for

first

2

tankfuls.

Mix

in

a 50:1

rati

0

therea

fter.

'.,g;.,

~

3.

Keep

cooling

fan

belt

tight.

See page 5. .

4.

Proper

break-in

is

critical.

DO

NOT

exceed

40

mph

for

the

first

25

miles,

nor

force

machine

at

full

throttle

in deep snow.

An

occasional

burst

of

full

power

on

hard packed

snow

will

not

be

harmful.

'"

5. Always warm-up

engine

prior

to

making

a

high-speed

run.

FAN

BELl

TENSION

A loose cooHng fan

belt

wfll

sltp

re-

su

lt

i

ng

in

an

overheated

en

.g,

i:;ri

e.

RellX)Ye

fan

gua

rd

and

c.rreck

fan

belt

t.ensi

~

pn

frequently.

Deflect belt

by

hand

midway

between

sheaves.

If

deflection

exceeds

3/8-

inch, tighten

belt

by

removing

shim(s )

from

between

upper sheave halves.

PTO

SEAL

GUARD

The

340

RS/2

engine

ha

s a guard

which

prevents a

failed

drive

belt

from

damaging

the

PTO

end

seal.

When

installing

seal guard,

center

hole

in guard

around

crankshaft before

tight-

ening screws.

This

will prevent

g~~r.d

from

contacting crankshaft.

- 5 -

- - ----

--

_.

FLYWHEEL

REMOVAL

A

F1.ywhee

1

H~

~

':

":

!!l

"j!:e

:

o:i!

(J

DM-

64-1) is

required to

ha

j.

,: i

f.1

,

§'w

;

he

'el

from

rotating

when

r~rr¢vi

:'

n,g

;

0;1"

~

iMs

..

t-~

'

Hi

'

ng

flywhee 1

reta

itlii1g

·

nlr1~

:

,.

.'

A'l

s

'

0

use ho,lidi ng tool

with

puller,

'

,rs

shown

above,

when

pulling f1ywheel.

IMPORTANT:

Do

not

stri

ke

flywheel with

mallet,

as

this

can cause permanent

disto

rt

ion.

Torque

flywheel

retaining

nut to

60

ft-

lbs.

FUEL

S

YST

EM

CARBURETOR

r

-

~=

=

___

-_

-_-_

-_-

_-_-

_-

::

_-

___

~

-.

~

_<?i

_-_

-_-_

~

-_

~~~

___

=

~

_-

_

~

=

=~

~

-:

I , I

I , '

!

i

~i

I I I

I : : :

: : I :

I t I I

I I I I

I : I I

I I I 1

I I I

Starter

:n:

plunger:

:

, :

, ,

Throttle

valve

Float

,

I I

I '

I :

, ,

Starter

jet

Fuel

..

Air

CJ

Mixture

¢ri

Jet

needle

Pilot

jet

Ring

The

function,s of the

Mikuni

carburetor

can

be

divided

into

the following:

Pilot

system,

main

system,

float

system

and

choke

syste~.

PILOT

SYSTEM

(IDLE)

The

pilot

system

con

s

ists

of the

air

jet,

pilot

jet,

air

screw,

pilot

outlet

and

bypass.

The

ratio

of the

air/fuel

mixture

is

controlled

by

adj.ustingthe

air

screw.

MA.IN

SYSTEM

The

main

system

consists

of the

jet

needle, needle

jet,

main

jet,

and

throttle

valve.

The

ratio

of

air/fuel

mixture

is

controlled

by

the

size

of the

main

jet.

FLOAT

SYST

EM

The

float

system

consists

of (2) independent

floats

and

needle valve.

The

indepen-

dent

float

system, along with a fuel surface

stabilizing

plate,

maintain

and

stabilize

the fuel

at

a constant

le

v

el.

CHOKE

SYSTEM

(Fuel Enrichener)

The

choke

system

consists

of the

starter

jet

and

starter

plunger. This system

meters additional fuel through a separate system, thus

eliminating

the

need

for

a

choke

valve in the

bcire

of the carburetor,

which

reduces carburetor

efficiency.

1. Swivel Adapters

2.

Lock

Nut

3.

Cap

4.

Gas

ket

5.

Throttle

Valve

Spring

6.

Pl

ate

7. E-Ring

8.

Jet

Needle

9.

Throttle

Valve

10.

Needle

Jet

11.

Starter

Plunger

Cap

EXPLODED

VIEW

OF

MIKUNI

VM

34-68

18.

Thr

,Q,

ttle

Stop Screw

19. Stop Screw Spri

ng

2a

.~;Q.~

t

~

"

e

:

t

J

~

?

~

W;e

,d)

21. iB'a;

.f.;lfd

fe

'"

P'l atte

22.

pfj

il1

af

J'e't

..

23.

Gasket

24.

Needle Valve Assembly

25.

Float

Arm

26.

Float

Arm

27

.

float

(2

us

ed)

28. Ri'ng

12.

Starter

Plunger

Spring

29.

Main

J.

et

(See pages

10

&

11)

_

13.

Washer

Plate

30.

Float

Body

14.

Starter

Plunger 31. Drain Plug Gasket

15. Air

Screw

16.

Air

Screw

Spring

32.

Drain Plug

33.

Air

Jet

(1-4)

17.

Body

34. Screw

(4

used)

ADJUSTMENTS

CHOKE

SYSTEM

ADJ

USTMENT

The

choke

sys

tem m

eters

a<

dd5ti

an

a1

fuel

for

starting

a

cold

engine.

As

the

system

re

qu

ires

ne

,g

...

a,t,iv.e

press

ure in

ord

er

to

func

ti

on,

:e:fu

:

~

',

t'hi

tottl

e must be

c1

os

ed

when

s

ta

rt

i

;

n

~

~r

~'

.

Adjust choke

sy

-

sterna

::

$.

f,bTlows:

1. P

ositi

on

cho,

ke

'le.ver t

oo

das

h)

down

.

2.

Look

in

the

sta

'

rter

plunger

hole

(3

o'clock

pDsition

in

the

carburetor

throat)

. The

starter

plung

er

should

be

all

the

way

down

in

its

bore

(seated)

.

3.

If

not,

1005

en

jam

nut

(A)

an

d

turn

adjusting

nu

t

(8)

clockwise

to

brin

g

the

star

t

er

plunger

down.

Adjust

to prov

ide

slightfreeplay

at

lever

(on

dash).

Tighten

jam

nut.

4.

Pul

l choke

le

ver

(on

dash)

up.

Look

in

to

the

starter

plunger

holes (3

o'clock

posit

ion).

Plungers

should

have

raised

and exposed

at

le

ast

50%

of

the

ho

1es . If

not,

too

mu

ch

free

-

play

was

allowed

in

step

3.

IMPORTANT:

If

the

starter

plungers

do

no

t

properl

y

sea

t,

the

carbureto

r

will

r un RI

CH,

affecting

the

main

syste

m.

Be

certain

choke lever (on

dash

r has

slight

freeplay

wherr

star

ter

plungers

are

seat

ed.

FLOAT

LEV

EL

ADJUSTMENT

I

Ih

I ' '

i;

I 4

~

:~~--1--

1

I I

'O

.

90±.O

IN

_

i;

~

_

I , - 1

I I '

-+-

-----

,-

~

,"

-

..

-,

'-

-j

;

I i

L 1 .- -

j---

~

l_r-:,7

, i

'l

i

l~

1._,,--

,,_

V J ;

Check

float

adjustment

as

follows

:

1.

Remove

the

float

chamber body and

g~sket

from

the

carburetor.

2.

Invert

the

carburetor

and

meas

ure

tf

distance

from

the

baffle

plate

to

the

top

edge

of

the

float

arms . The

distance

should

be

0.

90

+ .

04

-

inch

(23

mm)

.

3.

Bend

needle-valve

actuating

tab,

if

,

necessary,

to

mak

e

adjustment.

JET

N

EEDLE

ADJUSTMENT

The

jet

needle

can

be

set

in one

of

5

different

setti

ng

s

to

fin'!: tune t

he

midrange

mixture

.r

atiD.

This

sett

ing

does not

affect

idle

or

full

speed

operati

on.·~

'

'*

The

E-ri

ng

is

fac

tory assembled in

groove

No.3

. Groove

No.

1 provides

lean

er

midrange

operation

; groove

No

. 5

provides

riches

midrange

operation

.

SYNCHRONIZING

THE

CARBURETORS

1.

Turn

the

throttl

e stop screws

(A)

counterclockwise

until

the

screw

tips

are

flush with the inside of

the carburetor bore.

2.

Loosen

lock nuts (8)

on

throttle

cables a

nd

turn swivel adapters

(C)

clockwise

until

the

throttle

valv

es

fully

seat

in the carburetor bores.

3.

Turn

the

throttle

stop screws

(A)

clockwise unti 1 they

contact

the

throttle

valves .

When

the screws

contact the v

alves.

the

valves will

begin to

ri

se.

Then

turn the stop

screws

(A)

two

additional

turns

clockwise.

4.

Carefully

seat

air

screws

(0).

Back

out 1-

1/8

tur

ns couhterclockwise.

5.

Start

and

warm

up

engine.

Tu~n

throttle

stop screws (equally) clock-

wi

se

to

raise

idlespeed;

counter-

clockwise to

low

er

speed.

Idle

speed

should

be

22

00

-2600

rpm.

S

Tt)

P

SCRE~

!

6.

Op

;

en

clir flow control

and

place Air

F]owMeter .

(JDM

-

64-'2)

.over

car~uretor

tliroat.

Tub

.e must

be

Tn

a

vert

1

ca

1

pas

Hion.

7.

Slo.

wly

close

air

flow

control

until

float

(in

tube)

lines

up

with a

graduated

mark

on

tube.

8.

Place

air

flow m

eter

on

second carbu-

retot.without

changing adjustment

of

a·

fr

flow

contra

1.

.

9. AdJust

throttle

stop screw

on

second

G:

aW

,Quretor

to

bti

'

ng

float

to

same

level

as

ins

tep N

o.7.

Shut

off

eng

n"ne.

10.

Turn

the swivel adapters

(A)

counter-

clockwise

until

all

slack is

removed

from

the

throttle

ca'

bles.

Tighten

th~lock

nuts (B).

11

.

S

'

i

~

owJy

compress the

throttl

e 1ever

on~he

handgri

p.

Both

throttl

e

va

,liY'e;$ should begin to

rise

at

ex

act-

ly

the

· sa:

rhe

time.

If

not, repeat

step

Hk

12.

Support machine

so

track

4s

off

grouncl.

Start

engine

and

run

at

4XHi)Q.rpm.

Place a

wedge

in

throttle

l

~

ev:~

'

r

to

rna

inta

in engi

ne

at

th

is

rpm.

13.

Use

Air

Flow

Meter (as in .Steps 6-9)

to determine

if

carburetors a

re

synchronized

at

this

rpm.

If

not,

turn swivel adapter

(A)

clockwise

on

carburetor with highest float l

ev

el

until

float

levels

match.

- 9 -

MAIN

JET

SELECTION

The

main

jet

meters fuel through the

carburetor

when

operating

in the 1/2

-to-

full

throttle

range . Temperature

and

altitude

·

afject

the

density

of

air.

In

order

to

maintain a

constant

air/fuel

ratio,

which

results

in

peak performance, the

carbur

tors

mus~

be

jetted

richer

or leaner for varying

conditions.

The

follo

wing

chart

matches

jet

sizes

(Mikuni

No

.)

with

conditions.

Note

that

th

1eft-hand

ca

rburet

,

or

is

always

jetted

one

number

richer

than the ri ght-

hand

carbu

retor.

As

the

left-hand

cylind

er

is

farther

from

the

cooling fan, t

hi

s

is

necess.

to

ma

intain

uniform

cylinder

te

mpera

tures.

TEMPERATU

RE

(Deg

rees F)

-

40

0 to -

20°

-

20

0 to a

a 0°

to

40

0

40°

to

80

0

Above

80

°

Left

Ri

9ht Left Right Left

Ri

gh

t Left Right

Left

Right

ALTITUDE

Carbo

Carb o

Carb

o

Carbo

Carb

o

Carbo

(Feeti)

240

230

230 220

220 210

210

200

---

8000

-10,000

250

240 240

230 230

220

210

200

6000

-

8000

260

250

240

230

220

220 210

4000-6000

270

260

260 250 250

240

230

220

2000-

4000

2

80

270

270 260

260*

250

*

250

240

240 230

Sea

Level

*Factory

Installed

. See page

11

for

jet

availability.

NOTE

:

A.6

a

fr{.nct.£

chec

k.

on

j

et

,6e.1.ec;UoYl.

,

lLemove

.6pevz.R.

pwg/s

a6.ten..

mafUng

a

lugh

.6pe.ed

1LUYl.

.. SpMk.

pwg

.6houJ!..d

appeaft dMk. bMwn.

Aught

bILOWl1

cololL

wouJ!..d

-<-Yl.cUc.a-t

c.alLbUJl..e.tOM

Me

je.t.ted

,too

LEAN;

bfa

..

c.!?

woU£d

-<-Yl.d-<-ca.te

:too

RICH

. '

.I

-

10

-

MAIN

JETS

AVAILABLE

Mikuni

John Deere

How

Number

Part

No.

Obtai

ned

200

M65471

Order

From

Paris

210

M65472

Order

From

Parts'

220

M65852

Order

From

Parts

230

M65882

In Storage

Compartment

240

M65853

In Storage

Compa

:rtment

250

M65854

Factory

Installed

R.

H.

Carburetor

260

M65855

Factory

Installed

L.

H.

Carburetor

270

M65883

In Storage

Compartment

280

r~65884

In Storage

Compartment

NOTE:

The.f.aAg

eA

;the

M-iJ<.wU..

numbeh

J

.:th

e.

,taAg

eA

;th

e.

j e;t

OJU

fJ.-c:.e,

w1U.c.h

wd

t

phOv-ede

a.

Jr.J..c.heJ1.

Uh/6uet

rrKx;tMe.

The

Mikuni

number

is

st~mped

into the

bottom

of the

jet.

This

number

is

a

measure of fuel flow

and

is

not

associated with

ari

exact

orifice

size,

-

11

-.----

-

--

- -

------

----

- -

To

c-

ha

'

nge

plug

fr

·

0m

be

'r b0Qy.

mai

n

jet.

CHANGING

MAIN

JET

MAIN

JET

DRAIN

PLUG

th

-e

rna

in

jet)

remove

the drain

the

bottom

of

the

float

cham-

This provides access to

the

H£AIlL

lGUT

DWlIER

SWITCH

Y-

U

o·

...l

OJ

LIGlIT

SIX

LTCH

COUPLER

ELECTRICAL

SYSTEM

WIRING

DI

AGRAM

BROWN

/1.'lllTE

BROlo/N

/WHITE

BLACK

Ace

COUPLER

TETHER

B

ROWNNHI,-.T_E

_ _ _

,-,

,

BRO\.JN/I<HITE

SWiTCH

COUPLER

WHITE/BLACK

TAlI.

LICHT

COUPLER

o

VOLTAGE

RECUL\TOR

WHITE

EMERCENC-"Y

STO

P

SW1TCH

COUPLER

RED

I.fHTTE

BLACK

o

MODULE

NOTE

:

(

",L

t .

Th

e w

.uung

haAne6/.)

on

the.

JD

340/S

hew

f'W

pJr.ovi,o,i,.OYL:O

~oJr.

an

ue.c..bUc

/.)t.cuz;t

- 12 -

/

;

:::-

.;.~

:'?

~

;:::-;

....

r:-- '"

1.

Magnetic Flywheel Rotor

2.

Ignit

i

on

Timing Rotor

3.

Alternator S

tator

4. I

gn

itio

n Timing

Ring

IGNITIO

N

SYSTEM

5.

Electronics

Module

6.

Ignition

Transfor

mers

(C

oils)

7.

Surface

Gap

Spark Plugs

Princi"

ple

of

Ope

r

ati

on

The

Prestolit

e

Electr

omag

C.O.

ignition

system is a combination permanent magnet

flywheel

alternator

and

solid

state

capacitor

discharge

ignition

system.

The

electromag is des i

gn

ed

to supply the

hi

gh

voltage of

the

tgnition

system as

wel

l as

as genera

te

the

curren

t

required

for

lighting

sys tems,

In

operation,

the flywhe

el

rotor(l),

which

incorporates a

special

f

lexible

ma

gnet

an

d

is

mounted

on

the

engine cranksh

aft,

revolves around

the

alternator

stator

(3)

which

is

fixed to the engine. Current is

gen

erated

in

the

windings

on

the

twe

lve

poles of the

stator

pla

te,

nine of

which

supp

ly

power

for

the

lights

and

three

of

which supply

power

for

ignition.

The

electr

onic

module

(5) incorp,'Orates the

ignit

ion

capacitors

and

the

necessary

solid

-~

tate

"

ci~cuitry

!o~

cha~gin9

and

~ischargin

g

~hem.

The

timi

ng

rotor

(2)

revolvl

ng

wlth ln the tlmlng rlng (4)

trlgg

ers the

dlscharge

of

these

capacitors

through the

electronic

box

to

the

ignition

transformers

(6),

\--Jhich

"step

up"

the

vo

ltage

to a level necessary to insure successful

firing

of

the

surface

gap

spark

p

lu

gs

(7)

.

-

13

-

/). CAUTION:

High

~nergy

Ignition

S~s-re:n

c~n

produce

injurious

ele~trical

sho~k

.

~

Always s-rop

engine

and remove

teTher

sWitch

or

key

before

touching

or

working

on any

ignition

system

parts

. 00 no-r ho

ld

spark

plug

,

leads

or

connedors

in

hand

to

check

for

spa

rk

.

PRELIMINARY

CHECKS

Check

all

plug-in

connec

tions

to

make

certa

i n they are

clean

and

ti

ght.

Check

al l leads to

make

certain

one

is

not

brok

en

or

has

rubbed through the

insula-

ti

on

and

is

groundi

ng

out.

Since the

ignition

system

and

charging

system operate independent

of

each

other,

the trouble shooting

and

service

proce-

dures are separated

into

their

respective

sections.

TROUBLE

SHOOTING

THE

IGNITION

SYSTEM

Disconnect a spark plug wire

from

one

cylinder

and

connect

it

to

a

test

spark

plu

g.

Place

test

plug

on

cylinder

cover

to

ground

plug .

Do

not

hold in

hand

.

Plug

in

the

tether

sw

itch,

then pull the

s

tarter

and

check

for

a

spark

at

the

test

plug . Test both

cylinders

in the

s

ame

manner

.

If

sparks

are

observed

at the

test

plug

for

bo

-

th

cylinders,

the problem

lies

elsewhere

in

the engine

(ca

rburetion,

timing, or mechanical

fail

ure ).

1.

If

a spark

discharge

is

observed

at

on

e

cylinder

but not the

other,

the

problem

lies

in

the

coil

or high

tension lead , the timing

ring,

or

the

electronics

mod

ule.

The

eas

iest

met

hod

for

locating

the

fa u1ty

component

is

to use

an

ohmmeter

a

nd

measure res i

stances

. See

ohmmeter

test

procedure for

resis

tance

valu~s.

Howe

ver,

if

an

ohmmeter

is

not

available,

t

he

following

test

procedure can

be

used

.

A,

Coil Test -Disconnect

the

primary

1

ead

from

the nonf;

rJ...D..9.

coi 1 (red

or white

lead).

Disconnect the

primary

lead

from

the

firing

coil

and

install

it

on

the

nonfiring

coi'l.

Do

not

hold

the primary lead

on

the

co

il

primary terminal

as

a se

y.

ere

e

lectri

cal shock

may

res

ult.

Plug

in the

tether

switch,

and

pull the

s

tarter

,

If

the

nonfiring

coil

now

produces a spark ,

the

coil

is

good.

Rec

onnect the primary leads to the

proper

co

il

s a

nd

proceed to timing

ring

test.

If

the

nonfiring

coil

still

does not

~

roduce

a

spark,

the coil

is

defective

and

must

be

replaced.

(Check

high

tension

lead

before replacing

coil.)

TO

TI

MING

RING

ASSY.

JUMPER

LEADS

8, Timing

Ring

and

Electronics

Module

Jest

-

Make

three

short

jumper leads

terminated with

one

ma

le

and

one

female

bUllet

-type connector to

mate

with the

terminals

in the connectors

at

the

electronics

module. (Jumper

leads with small

alligator

clips

could

also

be

used.)

Unplug

the

two

con-

nectors

(leading

to timing ring)

from

the

electronics

module. Connect the

three

jumper leads as

shown

above.

Be

certain

connections are

good

.

Plug in the

tether

switch

and

pull

star

ter.

If

the

nonfiring

coil

now

produces a

spark,

the problem

lies

in

the timing

ring

and

it

must

be

replaced .

If

the

nonfiring

coil

still

does not produce a spark, the

problem

lies

in

the

electronics'

modu'le

and

it

must

be

re'placed.

IMPORTANT

:

00

not

operate

thes

tarter

with the

plug-in

connectors completely

disconnected

from

the

electronics

module,

Internal

damage

can

result

to the

e

lectronics

module

.

2.

If

spark discharges

are

not observed

at

either

cylinder,

the

system

will

have

to

be

tested

wi

th

an

ohmmeter,

or

checked

by

replacing

components.

However

, before

testing

the

system,

make

certa

in the

"ON"

-

"OFF

It

swi

tches

(tether

switch

and/or

kill

switch)

are not the prob1

em.

Di

sconnect the

large w'

hite

coupler from

the

engine,

and

again check

for

spark discharges

at

the

test

plug(s).

OHMMETER

TEST

PROCEDURE

JVjake

certain

the ohmmeter bei:

ng

used

is

accura

te

and

the

batteries

are

fresh.

Pe

riodically

zero

the

meter during the

tests,

and

a1so zero meter each time a

change of

scale

is

made.

~0703:>-

OHMS

1.

Unplug

the

two

connectors

(leading

to

timing ring)

from

the

electronics

roodule

and

make

the following checks

at

the connectors

on

the

wiring har-

nes s

as

shown

above. Connect the

ohmmeter

1eads between the red 1

ead

terminal

and

the white lead terminal .

The

ohmmeter

should

ind~cate

between

100

and

300

ohms.

Connect the

ohm

-

meter leads between the white lead

terminal

and

the black lead

terminal.

The

ohmmeter

shoul d i

ndi

cate

betv/een

100

and

300

ohms.

-

15

..

Connect

one

ohmmeter lead to the engine

block.

Then

check

the

three

terminals

with the

other

ohmmeter lead.

The

ohm

-

me

ter

must

indicate

an

open

circuit

(infinity)""at

all

three

terminals.

If

the above

readings

are

not obtained,

the timing

ring

assembly

is

defective

and

must

be

replaced.

2.

Unplug

the

connector

(leading

to

alternator

stator)

from

the

electro-

nics

module

and

make

the

.following

checks

at

the

connector

on

the wiring

harness

as

shown

above.

Connect

one

ohmmeter 1

ead

·to a

good

ground connection

on

the

engine

block. Connect

the

other

ohmmeter

lead

to

the

black lead terminal .

The

ohmmeter

should

indic

ate

between

30

an

d

100

ohms

.

Remove

the

ohmmeter

lead

from

the

black lead terminal

and

connect

it

to

the

white lead

te~minal.

The

ohmmeter should

indi-

cate

between

2000

and

3000

ohms.

(Cha

nge

scales

and

reset

ohmmeter

to

ze

ro

if

necessary.)

If

the above

readin

qs

are

not

obtained.

the

stator

assembly -iS

defective

and

mus

t

be

replaced .

o ©

COIL

3 .

Check

each coi 1 sepa

rately.

Rem(ove

d

the primary lead

from

the

coil

re o

or

whi

te lead) .

Connect

one

ohmmeter

lead

to the

primary terminal

stu

d

on

the

coil.

Connect the

other

ohmm

eter

lead to

the ground

co

nn

ectio

n

at

the

coil

as

s

hown

above

.

The

ohmme

ter

should

indicate . 1 to .5 o

hms.

Because of

the

low

primary

resista

nce

make

certa

in the

ohmmeter

has been

set

to

zero.

Remove

the

ohmmeter

lead

from

the

primary terminal

stud

and connect

it

to the spark plug wire

te

rminal .

The

ohmmeter

should i

nd

i

cat

e

100

to

300

.

ohm

s.

If

the above readings

are

not

obtai

ned

the coi 1

is

de

fective

and

must

be

replaced .

Use

the

same

pro-

ce

dure to

test

the

other

co

i

1.

(Check

high tension lead

before

replacing

co

i 1.)

4. If a

11

tes ts to thi s poi

nt

have been

within the

listed

spec

ifications,

the

troub le presumably

lies

in the

ele

c-

tronic

module. Because of the

many

var

iables

involved

whe

n

testing

f"

solid

state

componentry wi th

an

ohmmeter,

eh

ck

the

electronic

mo

dule

by

re-

placement only .

TR

OUBLE

SHOOTING

THE

ALTERNATOR

SECTION

The

alternator

can

be

tested

for output

using

either

an

AC

voltmeter

or

a

60

wa

tt

125

volt

light

bulb with

test

leads .

In

order

to

test

the

alternator

it

will

be

necessary

to

di

sconnect the

two

.

gr

een/ye1

low

leads from

the

system

Wl

r-

ing . A prelimi·

nary

check

of

the

alter

-

nator

can

be

ma~e

with

an

ohmmeter

to

det

ermine

if

the

leads

or

stator

are

ope

n or grounded .

The

resistance

of

the

stator

assemb

ly

should

be

0

.2

to

0.6 o

hm

when

checked between the

two

gr

een/yellow

leads.

The

?hmmeter should

read

infinity

whenchecklng

between

ei

ther

lead

and

the

engine housing.

No

reading across

the

two

leads

wo~ld

indi -

cat

e

an

open

circuit

and

a readlng

fr

om

eit

her lead to ground would

indicate

a

ground

ed

circuit.

If

a.prob

lem

is

indi -

cated , check the

lead

Wlres

for

worn

or

broken

insulation

or

a broken le

ad

.

TESTING

OUTPUT

-

AC

VO

LT

M

ETER

Conne

ct

the

AC

voltmeter

to

the

two

green/yellow

leads

as

shown

abo~e.

Start

the engine

and

run approxlr

na

tely

4000

rpm

. ·

The

AC

voltmeter

should in -

dicat

e

40

to

70

volts

.

TESTING

OUTPUT

-

TE

ST

BULB

Co

nnect the

test

bulb to the

two

green/

ye11o\'1

leads.

Start

the

engine

and

run

at

approxima

tely

20

00

rpm.

The

test

bulb

shoulQ

have a

soft

orange

glow

.

The

bulb should

get

brighter,

as

th~

.

engine speed

is

incr

eased.

At

approxl-

mately

7boo

rpm

the

bulb should

be

about

normal

brightness

.

-

16

-

,,-,

._

....,

_._

•.

_-----

-----

""

.-

SPARK

PLUGS

-

17

-

BRAND

PART

NUMBER

AC

.,;

SV4XL

(AM53223)

Champion

N-19V

(AM53187)

Surface

gap

spark plugs sometimes

have

a sooty appearance. This does not

mean

the plug

is

malfunctioning,

as

CD

igni-

tion

is

capable

of

firing

a plug of

this

type.

If

the

insulator

around

the

center

electrode

appears IItracked

ll

or cracked,

the plug should

be

r~placed.

If

external

insulat~r

is

cracked,

the

plug should

also

be

replaced.

If

the spark plug

center

electrode

is

burned back

1/32-inch

below the

insul~tor,

replace the plug.

00

not replace plug

unless

this

condition

exists

or

the

insulator

is

cracked.

IGNITIO

N

TIMING

Check

and

adjust

igni

tio

n

timing

as

follows :

~~

~

"

DIAL

;:

?

\

~INDICATOR

;

,

1.

Remove

recoil

st

art

er.

Bend

a loop

in

a small

finish

nail

and

secure

nai l to fan

cover

w

ith

a cap screw.

Point

on

finish

nail

should

just

miss

edge of sheave as

shown

above.

2 .

Install

dial

ind

icator

in

No

.1

spark

plug

hole.

3. Rotate

crankshaft

to

locate

TOC

(Top

Dead

Cen

ter

)

and

"z

ero

"

dial

indica-

tor.

4. Rotate cranks

haft

coun

terc

l

ockwi

se

(opposite

normal

rotation)

until

dial

indicator

reads

.OgO

-

inch

BTDe

(Before

T

op

Oead

Center).

5.

\~ith

flywheel

in

this

position,

plac

e

a

mark

(with

black

felt

pen) on sheave

rim

corresponding

wi

th

nail

point.

6. Re

mov

e

dial

indicator

and

reinstall

spark

plug. f

1.

CO

'

hn:e

~g

.t

'

a

,

timing

light

to

N

o.1

spar

plug le'ad a·

nd

to

a

12-volt

battery

as snown

above.

NOTE

: A

c.£:aJnp~OYl.

:type.

:t-Cm-LYl.g

.ught.

(.6u.c.h

a..6

MVt

c.-O-Tftonic.

Model.

712

p'<'c..:tuA

e

above.)

.-i:.6

pJte.~

,

eJt/1.e.d

.

CD'<'gr

U;t{.o

n.

c.an.

dccmag

:e a .

.6:Ut

,

nd'aJLd.

~Yl.g

ugh:t

.

2. S

ta

rt

engji'

ne

Cw

ith

rope)

and

run at

approxima;

'tely

4000

rpm

.

3.

Aim

timi'ng

light

at

nail

point.

Mark

made

on

sheave

should

align

wi

th

nail

po

i nt .

4.

If

not

, remove flywheel

and

alter-

nator

stator.

Loosen

(4)

screws

securing

timi

ng

ri

ng

and r

otate

as

neces

sary

to

advance

or

retard

timing.

Retighten

screws secu

rely.

5.

Rea

s.s,e

mb

.

le

and

recheck

timing.

-

18

-

P

OWER

TRAIN

CLUTCH

1.

Cap

Screw

(6 used)

7.

Guide Butt0 n

(6

u'S

'ed)

13

.

Pivot

(3

used)

2.

Pi

lot

Washer

8.. Roller

(3

used)

14

.

Steel

Washer

(6

used)

"P"

Cam

Arm

(3

used)

3.

Cover

Plate

w/Bushing 9 .

Steel

vJasher

(6

us

.ed) 15.

Steel

Washer

(3 used)

4.

Cover

10. Pin

(3

u

se

d)

16.

5.

Spring (Blue) 11. Spacer

Washer

(1

used) 17. Spring Pin (3 used)

6. Spider 12.

Movable

Face

wjBushing 18. Fixed

Face

w/Hub

The

l02C

John

Deere (Comet) Clutch

used

on

the

JD340/S

Snowmobile

is

similar to

the

100C

and

lOlC

Clu

tches.

However,

the following changes have been

made:

1. Duralon bushings

are

used in the

movable

face (key

12)

cover

plate

(k

ey

3)

and

rollers

(key

8)

.

2.

S

teel

vlashers

(ke.;-s

9 & 14)

are

used

rather

than nylon washers

on

each

side of

rollers

and

arms

.

3.

Arms

(key

15)

have a

"flat"

machined

onto outside

surface

to

"retard"

upshift

at

low

engine

rpm

. "

4.

Cover

plate

is

offset

, allowing

clutch spring (key

5)

to

ext~nd

throu

gh

cover. This provides

better

control of spring

tension

throughout

the

upsh

ift

range .

REMOVAL

AND

DISASSEMBLY

Use

same

procedures

and

tools

as

for

other

John Deere (Comet) Clutches.

Remove

plug

from

left

side

of

pan

to provide

access for

puller.

LUBRICATION

Dur~lon

bushings

do

not

require

lubrica-

ti

on

. U

se

;,

N,

e

N:

er-Seez Lubri cant

(PT569)

or

s

i

rf

C

Q

;

rl,

e

.

5

.

p

-

r:~y

:on

guide buttons (key

7),

cam

arms (key-15) a

nd

on

pivot

pi

ns

(

key

13).

NOT

E: U6e.

Loc.;t.f.;te.

(gitade.

AV

,

Red)

(AT

.t4927)

on.

.0

'(.J.'{'deA

-

to

-

Iw.b

tVul.e.acU,.

TIU..

/j-)...6

i'le.

C.e,/jI.,Cl.tl..!:f

to

rite.vent

,:~p'{'de./l..

oJwm

un.thlLe.aa-

,{.

H9

.

.tYl

u..o

e..

I t

may

b

e.

l

'te

c.e.MaJUj

to

.tOOM

'_Vl

Loc..t{;te.

wdh

hea.-t

wh.en.

fuaJ.J.6

e.mbuYl.g

uu

;tc.h.

- °i 9

..

john deer JD340/S User manual

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