Craftsman 636.796912 User Manual

owner's

manual

MODEL NO.

636.796912

CAUTION:

Read Rules for

Safe Operation

and Instructions

Carefully

êêl9501201

8619S01201 r/88

CRAFTSMAN

37.7 cc GAS POWER BLOWER

® Assembly ® Maintenance
® Operation «Repair Parts

Sears, Roebuck and Co., Chicago, III 60684 U.S.A.

PRINTED IN JAPAN

TWO YEAR LIMITED WARRANTY ON CRAFTSMAN

POWER BLOWER 636.796912

For tvvo years from date of purchase, when this POWER BLOWER is maintained, lubricated, and tuned up according to
the operating and mainlenance instructions in the owner's manual, Sears will repair free of charge any defect in material or
workmanship.
This warranty excludes blower pipes, spark plug, and air cleaner: which are expendable pans and become worn during
normal USB.
If this POWER SLOWER is used for commercial or rental purposes, this warranty applies for only 30 days from the date
of purchasa.
WARRANTY SERVICE IS AVAILABLE BY CONTACTING THE NEAREST SEARS SERVICE CENTER/DEPART­MENT IN THE UNITED STATES, This warranty applies only while this product is in use in the United States,

This warranty gives you specific legal rights, and you may also have other rights which very from state to state.

SEARS, ROEBUCK AND CO.
DEPT. 698/731A
SEARS TOWER
CHICAGO, ILLINOIS 60684

,4|li

INTRODUCTION

The Sears Power Blower, Mode! 636.796912 is a lightweight, high performance 2 cycle two stroke,

gasoline powered blower, which is designed for autumn leaves, driveway and sidewalk sweeping, gutter
cleaning, light snow and debris removal. The blower works faster and more efficiently than rakes or
brooms. Excellent balance, a vibration damping system and light weight ensure comfortable, safe
and fatigue-free operation.
This manual provides instructions for assembly, operation and maintenance for your unit. Be sure to

read this manual before operation.

IMPORTANT

RULES FOR SAFE OPERATION

1. Gasoline
(1) Handle gasoline with care. It is high inflammable.

(2) Use proper gasoline-oil fuel mixture. See P. 4.
(3) Refuel before starting work.
(4) Do not refuel a hot engine.
{5} Avoid spilling fuel or oil. Always wipe unit dry before using.
(6) Move at least 3 meters (10 feet) away from the fueling point before starting engine.
(7) Always store gasoline in approved container.

2. Operation

(1) Do not operate in unventilated area,
(2) Do not allow bystanders in work area.
{35 Always wear light clothing.

{4) Aiways wear safety glasses and a face filter mask.

Wear ear protectors where possible.
{5} Do not touch muffler, spark plug and rotating parts,
(6) Do not run the machine without flexible corrugated pipe and spent pipe or the engine

may be damaged,

(7) Do not use the machine in such a way that the end of spout pipe may be covered,
Check

ns Aiways check periodically for efficient and safe operation.
(2) Before Storing, drain fuel tank and carburetor.

(3) Wash air cleaner element with neutral detergent and dry it well.
(4) Remove dust from blower.

(5) Tighten bolts further if they are loose.
(6) Replace damaged parts.

(7) Always use proper parts for replacement.

SECTION i.
SECTION II,

SECTION ill.
SECTION IV,

SECTION V.
SECTION VI.

SECTION Vtl.
SECTION Vlil.

SECTION IX.
SECTION X.

SECTION XI.

TABLE OF CONTENTS

TECHNICAL SPECIFICATIONS ..........................

COMPONENT IDENTIFICATION

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

ASSEMBLY INSTRUCTIONS.............................

PREPARATION FOR USE
STARTING THE ENGINE
STOPPING THE ENGINE

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

..

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

.......

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

OPERATING THE POWER BLOWER ....

CHECK AND MAINTENANCE

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

STORAGE AFTER USE......................................

TROUBLESHOOTING , .,

SPARE PARTS LIST ...

........

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

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

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

.

..................................................... 4

..

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

.

. 4

................................................. . 5

.

..................................................... 5

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

........................................ 5

...................................................... 6

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

.

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

. 6

...................................................... 7

.

..................................................... a

......................................................10

Page

6

TECHNICAL SPECIFICATIONS Mode! 636.796912

Dimensions :

Weight, dry ;

Fuel capacity ;
Engine Type :
Displacement :

Ignition system ;

Carburetor ;

Spark plug ;
Spark plug gap :
Starter ;
Max. air volume :

Max. air speed :
Muffler :
Fuel :

*Specifications are subject to change without notice.

LxWxH = 450x490x495mmf17.7 in. x 19.3 in.x 19.5 in.)

8 kg !17.6 lbs.)

2.4 litre iO.634 gal.)
Air cooled two stroke

37.7 cc {2.3 cu.in.)
Solid State ignition

Float type
S.T.D. 360942

0.6-0.7 mm (.024 - .028")
Automatic recoil

11 m^/min. (385 cu.ft./min.)

83 m/sec. (273 ft/sec.)
Spark arrester

Fuel-Oil Mix Between 20 and 25 to 1

For the first twenty hours, use the mixing ratio of between 15

and 20 to 1

m. ASSEMBLY INSTRUCTIONS

1. Attach throttle lever to the machine. (Fig, 2)
Note; Ensure that the lever can be operated normally.

Screw

Figure 2

2, Attach shoulder straps to the machine. (Fig, 3}

Note: Adjust the straps to fit your body.

WARNING; Experience indicates that alcohol blended fuels

icalled gasohol or using ethanol or methanol) can attract
moisture which leads to separation and formation of acids
during storage. Acidic gas can damage the fuel system of an
engine while in storage.

To avoid engine problems, the fuel system should be emptied

before storage for 30 days or longer Drain the gas tank, start
the engine and let it run until the fuel lines and carburetor

are empty. Use fresh fuel next season. See Storage Instructions
for additional information.

Never use engine or carburetor cleaner products in the fuel

tank or permanent damage may occur,

CAUTION:

• When preparing fuel mixture, mix only the amount
needed for the job you are to do Do not use fuel mixture
that has been stored longer than two (2) months. Fuel
mixture stored lortger than this will cause hard starting

and poor performance, if fuel mix has been stored
longer than this time it should be removed and filled
with a fresh mixture.

• Use only a good grade of regular gasoline,

0 Use only a reputable brand of 2-cycle, air cooled engine

oil. Sears Chain Saw Oil is especially suited to this
engine,

• For the first twenty hours, use the mixing ratio of be
tween 15 and 20 to 1

Figure 3

3. Assemble blower pipes, (Fig, 1)

Note: Assemble pipes securely or they may separate

. while operating.

IV. PREPARATION FOR USE

1, Ensure again that all parts are assembled normally and

that all nuts and bolts are properly tightened

2. Adjust shoulder straps to fit your body so that pads rest

comfortably on your shoulder or you will be tired

3 Fuel and oil mixing

(1) Mixing ratio of fuel and oil: 20— 25:1

Example; 20 : 1 = gasoline 1 gal, : oil 7 oz,

25 : 1 = gasoline 1 gal, : oil 6 oz

(2) Pour half the gasoline into the container, add oil and

shake to ensure thorough mixing. Now add the
remainder of gasoline and shake again

Fill the tank with fuel without spilling.

4.
i1) Do not fill fuel above fuel limit level. (Fig. 4)

(2) Wipe all spilled fuel with a dry cloth,
(3) Always attach the fuel strainer, (Fig, 11)
(4) Tighten fuel cap securely,

uei limit level

Figure 4

V. STARTING THE ENGINE (Fig. 5 & 6)

1. Open fuel cock, (Fig 5)

2, Close choke Sever, (Fig. 5)

Note; In winter, close fully, but in summer or when the

engine is warm, open partly or fully.

Figure S

3. Push up throttle lever, (Fig. 7)

4. Holding the machine by your left hand and putting your
left foot on the machine frame, give a strong and straight
pull to recoil starter by your right hand. (Fig. 6j

CAUTION

Do not pull off rope, but return it gently with care.

UP (Highspeed)

“I“ Throttle lever

DOWN (Low speed)

StQPTOtfoffllM^ ’

Figure 7

VII. OPERATING THE POWER BLOWER

1, Adjust shoulder straps correctly to make the machine fit

your body .

2, After the engine fires, put the machine on your back

without inclining.

3. The velocity of air stream can be controlled from a gentle

breeze to a high-speed blast by throttle lever,

4. Select the best speed for each application of the blower.

Example: low speed for blowing dry leaves from lawn

and high speed for moving gravel or dirt from
driveway, (Fig. 8 & 9)

Figure 6

5. After the engine fires, open choke lever gradually to re
duce engine speed

6, Warm up the engine at tow speed

Note; winter: about 5 min. summer: 2 — 3 min.

VI. STOPPING THE ENGINE

1, Push down throttle lever to reduce engine speed.

2, Stop the engine by pushing stop button. (Fig. 7)

3, Put the machine down on the ground and close fuel cock.

CAUTION

о Do not point the blower pipe in the direction of people

or animals.

• Always wear safety glasses and use-a dust mask,
e Do not operate in unventilated area.

VIH. CHECK AND MAINTENANCE

1. Air cleaner (Fig. 10)
(1) Remove air cleaner cover and take out air filter.
(2) Accumuiated dust on the air filter will reduce engine

efficiency and increase fuel consumption,

{3} Wash air filter and dry it wetl,

CAUTION

Do not use gasoline and inflammable solvent to clean the

filter.

Air cleaner case

Air filter

Carburetor (Fig. 13)

4,

(1) Carburetor has been correctly adjusted at the factory

for optimum performance.
To adjust idling speed, turn the throttle stop screw

(2)

(turning it clockwise increases engine speed and
turning it counterclockwise reduces the speed).

Idling speed must be adjusted to me minimum

(3)

constant speed.

Figure 10

Fuel strainer (Fig, 11)
(1) Fuel tank is fitted with a fuel strainer located under

filler cap- Do not remove this strainer when filling
the tank.

(2) The strainer should be removed and cleaned at

regular intervals.

Fuel tank cap

'Fuel strainer

-Packing B

Figure 11

3, Spark plug (Fig. 12)

(1) Clean or replace the piug if fouled with oily black

deposits,

(2) Replace the plug if the center electrode is rounded

at the end or if the ground electrode is worn,

(3) Adjust the gap 0,6 — 07 mm ( 024 — ,028").

B, MUFFLER AND EXHAUST PORT (Fig. 14)

in the event that the engine should lose power and overheat,
the muffler should be removed and checked for excessive
deposits. Carbon build up in the exhaust port should be

removed with a piece of wood, removing that particles of

carbon deposits from the muffler flange area and wash the

complete unit in a suitable solvent.

Spark arrester

Screw

Figure 14

IX. STORAGE AFTER USE

5. Store the unit in a dry atmosphere and keep out dust.

1, Correctly preparing your Sears Power Blower for extend

ed storage will be amply rewarded by an increased service

life and trouble-free performance,,

2 Drain fuel tank and carburetor thoroughly,

Drain carburetor through drain cock,

3, Remove spark plug, pour one teaspoon of engine oil into

cylinder and pull recoil starter gently to distribute the
oil. Replace spark plug securely.

4. Thoroughly clean the unit and coat unprotected surfaces

with oil to prevent rust.

K TROUBLE SHOOTING

Refer to the chart to locate the problem and take the appropriate action.

Table 1

Fuel is not
reaching Fuel line hose clogged „ Clean.
carburetor

Fuel is not

— reaching -------------—^

cylinder

6

c

О I

Z ^

Ignition coil

-in good­condition

It is important to prevent gum deposits from forming in
essentia! fuel system parts such as the carburetor, fuel filter,
fuel hose^ or tank during storage. Also, experience indicates
that alcohol blended fuels {called gasohol or using ethanol or

methanoll can attract moisture which leads to separation and

formation of acids during storage. Acidic gas can damage the

fuel system of an engine while in storage.

To avoid engine problems, the fuel system should be emptied

before storage of 30 days or longer. Follow these instructions:

1

___ PisTon.& cytinder worn..,..

-----

Strainer dogged

i

-----

Carburetor out of order ,

, Wire connection defective .

High-tension cord

‘ connection defective

...........

...... Replace,

Clean.
Disassembie and check.

Heconnect
Repair as necessary.

.

Ш

’ ti

LI,

R

-No spark at plug -

X

ti

« c

X «

Û-0

«

Э

- c
о a

a

x: K

¡r 2

-If

. «

a

a

x:

H

Li

о
a

* w

Fuel does
not keep
funning

Accelera
tion and

low speed ­function
defective

Carburetor _

overflow

Engine does
' not crank *

. Insulator cracked
. Spark gap incorrect.
. Covered with carbon
, Fouled with fuel

Starting procedures

■ incorrect
Fuel valve clogged with

dust .............

Fuel passage in carburetor
clogged with dust

□

Fuel leaking from fixing

■ surfaces of carburetor
Carburetor does

■ not work normally
Crankcase and cylinder

‘ pressure leaks

Fuel inlet needle valve

- clogged with dust

Exhaust pipe sticky

■ with fuel

. Searing damaged ,

■ Piston and cvlirtder seized.
, Crankshaft worn

’ crankcase

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

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

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

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

Crankshaft contacting

.

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

_____

, Replace plug.
, Adjust.
, Clears or replace.
. Clean or replace.

. Start correctly

. Clean,
. Disassemble and replace

, Retighten.

, Replace,

.........

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

.. Stop leakage,

.

.. Clean.

This is because fuel mixture

is too rich,

■ Start the engine several times
with choke lever fully open.

_____

, Disassemble and replace
. Disassemble and replace,
. Disassemble and replace,

, Disassemble and replace,

Table 2

3

U»

.£

•o ­a

n

c

'm

c

m

. Engine

overheatsd

. Firing function.

defective

, Carburetor _

defective

_ Other

troubles

Improper fuel, used

Spark plug defectiva

' ibumt!

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

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

As cooling fins dog, air

' does not pass well '

Excessive deposits itt

■ combustion chamber

. Plug damaged or fouled..,,...... Replace or clean.

Combustion poor due to , . .
defective wiring ’

Needle setting

'incorrect

Carburetor overflow

. Air cleaner dogged

Compression insufficient

(piston ring stuck or

worn out)
Cylinder chrome plating

' peeled or worn out ......................

Exhaust port dogged with

' carbon

Throttle is not fully

’ open

Mvui Check wiring,

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

..

...........

...

..........

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

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

Use fuel with correct mixing ratio,

' ' Never use gasoline of poor quality.

...... Replace.

.

..... Clean fins,

....... Disassemble and remove carbon.

Readjust,,

........ Refer to Table 1,

Clean as necessary.

Disassemble, check and replace

, if necessary.

. Replace cylinder,

. Clean as necessary.

.

, Readjust,

SEARS POWER BLOWER PARTS LIST - MODEL 636.796912

Figure 15

SEARS POWER BLOWER PARTS LIST • MODEL 636.796912

Figure 15

KEY
NO.

1

2
3
4

S
6

7 NF04S-11Ì4 1

8
9

to

11

12
13

16
17
18
19

20
21
22
23

24 00218 0500 Q

25

26
27

28
29
30
31
32
33
34

35
36
37
38

39

PART

NO.

NF04S-01S0A 1

NFQ4S-1101-RB
NF04S.1102-RB
NF04S-1104F 1
NF04S-1107A 2

FL40-1109B-PB 1

NF04S.11I5

FH04S-1104

Ft40-1110
0420 22938 0
FL40-201IA-RB
FL40-2012A 1
NF40.2101A 2

EC024Ì83 1
EC02Ì44
FL40-3101A
FL40<S102
FL40-5011
FL40-5012
EC02-720
00113 0618 0
00165 0612 0 3

00218 0600 0
00218 1000 0
00227 0400 0
00310 0500 0
00311 0600 0
00311 1000 0
00312 0500 0
00312 0600 0
00320 0400 0
00320 0500 0 2
00320 0600 0 10
00320 1000 0
00431 0514 0
G0431 0512 0
00435 0518 0

QTY.

1

1

1

4

. 9

1
1 Nut (M4l
4

DESCRIPTION

Muffier mounting plate ass'y

1
1 Volute ease {rear!

!
1
1
1

1

1

1
1

5

8
1
4
4
1

1
4

1
7

Volute case {fronti

Bent tube

Screw (MS X 671

Engine cover
Impeller spacer
Cover

Plug

Impeller

Plug ¡rubberl

Frame compì.
Shoulder pad compì.
Vibrailon^jroof rubber

Fuel tank cap ass'y (Incl. 161
Packing A

Fuel tattk

Fuel-line hose
Throttle lever
Throttle ^Ire

■Stoptiution
Boll ÌM5 X 18!
Bolt (M6 X 12!
Nut |M5)
Nut ÌM6!
Nui^iM10)_3

Washer (M51

Washer (M61
Washer (MIO!

Washer !M51
Washer {MB!
Spring washer {M4!
Spring washer (M51
Spring washer <M6i
Spring washer {MIDI
Screw (pan head! (MS x 14!
Screw (pan head! (M5 x 12!
Screw ass'y (M5 x 18!

KEY

NO.

40 00431 0610 0
41
42 00626 3085 0
43 EC03-6103
44 ,
45
46
47
48 .

49
SO

51

52

PART

NO.

00431 0616 0

FL40-3103
FL40-9106
0561 13998 2
0641 27999 0

ECOSA-6111

HS021I-2028-RB
NB30K-6103 2
PS03-5111
00436 0512 0

QTY.

2
4
1 0 ring
1
1
1
2
1
1
2

1

I

DESCRIPTION

Screw (pan head! (M6 x 10!
Screw (pan head! (M6 x 16!

Fuel-line hose proieeiion tube
Plate
Labe!
Clamp (Hose! __
Fuel strainer

Packing
Plate
VibratiQO-proof rubber

Plug (rubberl
Screw ass'y

SEARS POWER BLOWER PARTS LIST-MODEL 636.796912

Figure 18

SEARS POWER BLOWER PARTS LIST - MODEL 636.796912

Figure 16

KEY

NO.

20

21
22
23

24

25
26
27

28
29
30
31
32
33
34
35
36
37
38
39

PART

NO.

1
2
3

4

S

6

7
8

9
10
11
12
13
14
15
16
17
18
19

EC044J72
0440 12999 J
0440 15997 1
060015988 0 2

EC034)71
0119 05994 0
0105 06934 0 6
EC044)125
EC03-109A
EC044191A

eC04-104c

eCQ3-115
0119 05995 0
EC04TÌ222
EC04-206/2B
EC04-207A
6C04-210A

0565 11999 0
0610 12996 1

EC0441516A
EC04-0S13A
A50103212700

243051821009

451050800009

A54103200100

A55003210001
A600032000QO
A60102600000
A56002600291

141051251002

A60S03210000
A57120950000

QTY.

1
1
1

4

1
1

1

1
2
4
1
1
1
2
2
1
1
1
1
4
4 Washer (M5)
1
1

1

1

1

1
1 Return spring

1

A57202700QOD 1
EC0443378
EC04-3122
00433 0520 0

FL40-9105/2A

1

1
3

1
EC044)71BA 1
11100100100

DESCRIPTION

Crank case ass'v (Ind. 2 ihru 7)
Oil seal (fronif
Oil seal iresri
Ball bearing
Crank case packing

Ì

Boll isockei head} (MB x 30}
Stud (M6)
Cylinder compì, (incl. 7)
Cylinder packing
Reed ass'v
Carburetor bracket
Reed bracket packing
Bolt (socket head! (MS x 18)
Crank shaft ass'v
Piston
Piston pin
Piston ring
Clip
Needle bearing
Recoil starter compì. (Incl. 21 thro24i
Recoil starter ass'v iincl. 25 ihru33)
Starter case B
Serev» IMS X 18}

Reel
Ratchet
Spiral spring
Friction spring
Friction plate
Bind screw (M5 x 12)

Starter rope
Starter knob
Mufller compì.

Mu!((or gasket

Screw ass'v (M5 X 20)

Label (model)

Magneto compì. (Incl. 39, 401

t

Flywheel

KEY

NO.

40
41
42
43
44
45 -

46

47
48

49

50
51
52
53
54 EC044)379ATA
55
56

PART

NO.

QTY.

11400331000

KM614388C

0650 14995 0
0170 08996 0
0203 08999 0
00218 0500 0

00310 OBOO 0

00320 0600 0 6
00434 0420 0
00532 0310 0
0566 05998 0
00310 0S00 0 1

0CM31 0510 0

00S32 0320 0

0043104100
0022704000

DESCRIPTION

1 Ignition coil
1
1
1
1

Plug cap
Spark plug
Nut (left) (MB)
Spring washer (M8)

6 Nut (M6)
1 Washer (M8)

Spring washer (M6)

2
1
1

Screw ass'v (M4 x 20)
Woodrulf key
Clamp
Washer (M5)

1
1

1

Screw (pan head) (M5 x 101
WoodruH key
Spark arrester

1 Screw (pan head) (M4 x 10)
1

Nut (M4)

SEARS POWER BLOWER PARTS LIST-MODEL 636.796912

Figure 17

SEARS POWER BLOWER PARTS LIST - MODEL 636.796912

Figure 17

KEY PART
NO.

1
2
3

A
5

6
7

a

9

^10

n
12
13

14 VM15/173
15

16
17
18
19
20

21

22
23

24

25
26
27
28
29
30

31

32
33
34
35
36

EC04-0682A 1
CK/31

832-16001
J8-3N05
MD14/40
VM14c1/38tJ
VM1S/24A
VM16/200
VM12/43
MD13/44
M21/15
VM24/148
N102-221

VMl 5/353
VM1S/264
VMl 5/351
VM13/139
BS2-00031
EC03-S0010
VM13/68A
VM13/326
82=43630
B34/83
VM13/215
VMl 5/331
VM18/164A
CW2»0416
VMl 5/348
VM13/210
CW2-0414
EC044)335B
0736 36998 0
00436 0410 0

EC04-3304A

EC04-3305

NO.

QTY.

1
1
1

1
1

1
1
1 Cap
1
1
1
1
1 Needle ass'y
1
1
1

1
1

1
1
1
1
1
1 Nut
1
1
2
1
1
2
1
1
4
1
2

DESCRIPTION

Carburetor compì. Unci. 2 !hni 31}

Cock body ass'y
Piston waive {#T.0i
Jet needle

E nng
Spring seat
Spring
Top

Cable guide
Cable gdjuster lock nut
Cable adjuster
Mam let (#77.51

Float arm

Float pin
Gasket

Float

Float chamber body
Guide screw ass'y
O ring
Clip
Bolt
Washer

Spring
Throttle stop screw
Spring washer cross screw
Gasket

Filter
Spring washer cross screw
Air cleaner ass'y Unci, 33,35, 361

Label

Screw ass'y (M4 x 10}

Air cleaner cap

Element

SEARS POWER BLOWER PARTS LIST - MODEL 636.796912

Figure 18

SEARS POWER BLOWER PARTS LIST - MODEL 636.796912

Figure 18

KEY

NO.

!

2
3
4

5

6

7
8

9

10

11

12

13 0715 06999 0
14 0713 21999 0
15

PART

NO.

NF04S-0903/1

FL40-9001

NF31-097B
NF04S-9121

FL40-9120
FL40-9121
NF40-7120

FL40-9012

FL40-9014

0717 04999 0

6619501201

0700 00994 0

0710 08999 0

QTY.

1
1
1
1

1
1
1
1
1

DESCRIPTION

Wing hose band (big!
Shoulder band ass'v
Wing hose band
Corrugated pipe

2

1
1
1 Plus driver
1

1

Straight pipe

End pipe

Hoso ctarop
Swivel joint
Tool kit {tncl.10,12 throlSi
Wrench Isocket head)

Owner's manual |FL40-9107/4i

Tool bag

Box wrenchS21 M/M)

Double-end wrench (8 x 10 M/Ml

OWNER^S

MANUAL

SEARS POWER BLOWER

The model number of your power blower is
located on the label on recoil starter of the
engine.
The serial number of your power blower is

located on the label on the fan housing.

MODEL NO.

636.796912

HOW TO ORDER

REPAIR PARTS

2.

When ordering repair parts, always give the

following information:

(1) IVJodel number:
{2) Name of item:

{3) Part number
(4) Part description

All parts listed may be ordered from any Sears
Service Center or most Sears stores.

(1) If the parts you need are not stocked

locally, your order wilt be electronically
transmitted to a Sears Repair Parts Distri
bution Center for handling.

636.796912

37.7 ccGAS POWER
BLOWER

6619501201 Sold by Sears, Roebuck and Co., Chicago, IL60684 U.S.A. Printed in Japan