Tecumseh VLV Technician's Handbook

Brand: Tecumseh

Model: VLV

Category: Engine

Type: Technician's Handbook

This handbook covers VLV40 - 675.

Other illustrated Tecumseh 2 and 4-Cycle Engine and

Transmission handbooks, booklets and wall charts are

available from Tecumseh.

For complete listing write, call or check our website at

www.TecumsehPower.com

T E C H N I C I A N ' S H A N D B O O K

TECUMSEH

Form No. 695578 Rev. 6/02 Litho in U.S.A.

ENGINES & TRANSMISSIONS

Tecumseh Products Company

Engine & Transmission Group

900 North Street

Grafton, WI 53024

Phone: 262-377-2700

FAX: 262-377-4485

Tecumseh Europa S.p.A.

Strada delle Cacce, 99

10135 Torino, Italy

Tel. 011 39 11 391-8411

Telefax 011 39 11 3910031

ENGINES & TRANSMISSIONS

www.TecumsehPower.com

VLV

(Vector)

4-CYCLE

ENGINES

IMPORTANT NOTICE!

SAFETY DEFINITIONS

Statements in this manual preceded by the following

words are of special significance:

WARNING

WARNING indicates a potentially hazardous situation

which if not avoided, could result in death or serious

injury.

NOTE

Refers to important information and is placed in italic type.

It is recommended that you take special notice of all

items discussed on the next page and wear the

appropriate safety equipment.

Before operating this engine it is your responsibility to

read this Operator’s Manual. Follow these basic rules

for your personal safety:

• Keep this manual handy at all times for future

reference.

• Read it carefully and familiarize yourself with

operating, maintenance, components and

safety instructions

Notice Regarding Emissions

NOTE

Engines which are certified to comply with California and

U.S. EPA emission regulations for SORE (Small Off Road

Equipment), are certified to operate on regular unleaded

gasoline, and include the following emission control

systems: (EM) Engine Modification and (TWC) Three-

way Catalyst (if so equipped).

Tecumseh Website

Visit the Tecumseh website at:

www.TecumsehPower.com

Table Of Contents

Chapter 1 General Information..........................................................................................1-1

Engine Identification .......................................................................................................1-1

Prior to 1999...................................................................................................................1-1

Short Blocks ...................................................................................................................1-1

Parts Identification..........................................................................................................1-2

Parts List.........................................................................................................................1-3

Oil and Fuel Specifications .............................................................................................1-4

Oil ...............................................................................................................................1-4

Fuel.............................................................................................................................1-4

Filling Fuel Tank .........................................................................................................1-4

Stopping the Engine and Short Term Storage................................................................1-4

Maintenance and Adjustments .......................................................................................1-5

Checking and Changing Oil........................................................................................1-5

Removing Debris from Engine....................................................................................1-5

Spark Plug..................................................................................................................1-6

Cleaning/replacing Air Cleaner...................................................................................1-6

Servicing Paper Filters ...............................................................................................1-6

Carburetor ..................................................................................................................1-6

Engine Speed.............................................................................................................1-6

Engine Stopping Mechanism......................................................................................1-6

Seasonal Storage...........................................................................................................1-7

Fuel System................................................................................................................1-7

Method 1.....................................................................................................................1-7

Method 2.....................................................................................................................1-7

Oil ...............................................................................................................................1-7

Lubricating Cylinder Bore ...........................................................................................1-7

Quick Maintenance Chart ...........................................................................................1-7

4-Cycle Engine Theory ...................................................................................................1-8

Intake..........................................................................................................................1-8

Compression ...............................................................................................................1-8

Power..........................................................................................................................1-8

Exhaust.......................................................................................................................1-8

Chapter 2 Air Cleaners.......................................................................................................2-1

General Information........................................................................................................2-1

Air Cleaner Service.........................................................................................................2-1

Polyurethane Pre-Filters.............................................................................................2-1

To Service Air Cleaner ...............................................................................................2-2

Carburetion.....................................................................................................................2-3

General.......................................................................................................................2-3

Identification ...............................................................................................................2-3

Float Bowl Service..........................................................................................................2-3

Rebuilding Carburetor Body .......................................................................................2-3

Removing Welch Plug ................................................................................................2-3

Chapter 3 Governors and Linkage....................................................................................3-1

General Information........................................................................................................3-1

Linkage Assembly/Disassembly .....................................................................................3-2

Governor Adjustment......................................................................................................3-2

Speed Controls...............................................................................................................3-2

Page

Page i

Chapter 4 Starters ..............................................................................................................4-1

Disassembly and Inspection...........................................................................................4-1

Assembly and Inspection................................................................................................4-1

Stylized Rewind Starter with Plastic Retainer.................................................................4-2

Disassembly and Inspection.......................................................................................4-2

Assembly and Inspection............................................................................................4-2

12 Volt Electric Starters..................................................................................................4-3

Removal .....................................................................................................................4-3

Parts List.....................................................................................................................4-3

Drive Assembly Service..............................................................................................4-3

Check Brushes ...........................................................................................................4-4

Armature Check..........................................................................................................4-4

Assembly....................................................................................................................4-5

Chapter 5 Flywheels...........................................................................................................5-1

General Information........................................................................................................5-1

High Inertia Flywheel ......................................................................................................5-1

Diecast Aluminum Flywheel ...........................................................................................5-1

Removal .........................................................................................................................5-1

Cored Holes....................................................................................................................5-2

Installation ......................................................................................................................5-2

Brake System .................................................................................................................5-3

Method 1.....................................................................................................................5-3

Method 2.....................................................................................................................5-3

Stopping the Engine......................................................................................................5-3

To Start Engine .............................................................................................................5-3

Wiring Diagrams .............................................................................................................5-4

Battery ............................................................................................................................5-4

Brake Pad Replacement.................................................................................................5-4

Brake Control Lever Replacement .................................................................................5-5

Control Switch ................................................................................................................5-5

Checking Control Switch ................................................................................................5-5

Chapter 6 Alternator...........................................................................................................6-1

Alternator........................................................................................................................6-1

Troubleshooting Electric Start Engines ..........................................................................6-1

Troubleshooting for Both Mechanical and Electric Start Systems..................................6-1

Chapter 7 Ignition...............................................................................................................7-1

Solid State Ignition..........................................................................................................7-1

Solid State Ignition Operation.........................................................................................7-1

Spark Plug Service.........................................................................................................7-1

Ignition Timing ................................................................................................................7-1

Chapter 8 Piston, Rings and Connecting Rod.................................................................8-1

Piston and Rings ............................................................................................................8-1

Connecting Rods............................................................................................................8-2

Chapter 9 Cylinders and Cylinder Heads.........................................................................9-1

Cylinder Service .............................................................................................................9-1

Reboring.....................................................................................................................9-1

Cylinder Heads...............................................................................................................9-1

Table Of Contents (Continued)

Page

Chapter 10 Crankshafts, Camshafts and Lubrication...................................................10-1

Crankshafts ..................................................................................................................10-1

Crankshaft Timing Mark ...........................................................................................10-1

Camshaft Removal .......................................................................................................10-1

Lubrication System.......................................................................................................10-2

Oil Pump.......................................................................................................................10-2

Chapter 11 Valves, Lifters, Spring and Valve Seats......................................................11-1

General Information......................................................................................................11-1

Valve Removal .............................................................................................................11-1

Valve Seats ..................................................................................................................11-1

Valve Adjustments........................................................................................................11-2

Valve Installation ..........................................................................................................11-2

Valve Lifters..................................................................................................................11-2

Oversize Valve Guides.................................................................................................11-2

Chapter 12 Oil Seal Service and Mounting Flange........................................................12-1

Oil Seal Service............................................................................................................12-1

Seal Replacement ........................................................................................................12-1

Chapter 13 Troubleshooting ...........................................................................................13-1

Table 1. 4-Cycle Engine Troubleshooting Chart...........................................................13-2

Table 2. Carburetor Malfunction Check Points.............................................................13-5

Table 3. Troubleshooting 12 Volt Starters ....................................................................13-6

Chapter 14 Engine Specifications ..................................................................................14-1

Torque Specifications ..................................................................................................14-2

Chapter 15 Education Materials and Tools....................................................................15-1

Tool Kit .........................................................................................................................15-2

Chapter 16 Sears Craftsman Reference Chart ..............................................................16-1

Decimal/Fraction Conversions......................................................................................16-2

Table Of Contents (Continued)

Page

Page iii

I. General Safety Precautions

A. Avoid Carbon Monoxide Poisoning

All engine exhaust

contains carbon

monoxide, a deadly

gas. Breathing

carbon monoxide

can cause head-

aches, dizziness,

drowsiness,

nausea, confusion

and eventually death.

Carbon monoxide is a colorless, odorless, tasteless

gas which may be present even if you do not see or

smell any engine exhaust. Deadly levels of carbon

monoxide can collect rapidly and you can quickly be

overcome and unable to save yourself. Also, deadly

levels of carbon monoxide can linger for hours or

days in enclosed or poorly-ventilated areas. If you

experience any symptoms of carbon monoxide

poisoning, leave the area immediately, get fresh air,

and SEEK MEDICAL TREATMENT.

To prevent serious injury or death from carbon

monoxide:

• NEVER run engine indoors. Even if you try

to ventilate engine exhaust with fans or

open windows and doors, carbon monoxide

can rapidly reach dangerous levels.

• NEVER run engine in poorly-ventilated or

partially enclosed areas such as barns,

garages, basements, carports, under

dwellings, or in pits.

• NEVER run engine outdoors where engine

exhaust can be drawn into a building through

openings such as windows and doors.

B. Avoid Gasoline Fires

Gasoline (fuel) vapors are highly

flammable and can explode. Fuel

vapors can spread and be ignited by

a spark or flame many feet away from

engine. To prevent injury or death

from fuel fires, follow these instruc-

tions:

WARNING

Read equipment manufacturer’s manual

and this material thoroughly before using

this engine. Failure to do so can result in

serious injury or death. Call Tecumseh

Products Company at 1-800-558-5402 if

you have any questions.

• NEVER store engine with fuel in fuel tank

inside a building with potential sources of

ignition such as hot water and space heaters,

clothes dryers, electric motors, etc.

• NEVER remove fuel cap or add fuel when

engine is running.

• Allow engine to cool before refueling.

• NEVER fill fuel tank indoors. Fill fuel tank

outdoors in a well-ventilated area.

• DO NOT smoke while refueling tank.

• Use only an approved red GASOLINE

container to store and dispense fuel.

• DO NOT attempt to pour fuel from engine.

Empty fuel tank by running engine.

C. Transporting Engine

DO NOT transport engine with fuel in tank. Fuel vapor

or spilled fuel may ignite.

D. Avoid Other Fires

To reduce the risk of fire, keep all materials that can

burn, including grass and leaves, away from muffler

and the rest of the engine.

E. Stay Away from Hot Surfaces

The muffler and other engine parts

become extremely hot during

operation and remain hot after the

engine has stopped. To avoid

severe burns on contact, stay away

from these areas.

F. Do Not Modify Engine

To avoid serious injury or death, DO NOT modify

engine in any way. NEVER tamper with the factory

setting of engine governor. Running the engine faster

than the speed set at the factory can be dangerous and

will VOID THE ENGINE WARRANTY.

G. Avoid Accidental Starts

To prevent accidental starting when working on equip-

ment, always disconnect spark plug wire and keep it

away from spark plug.

H. Stay Away from Rotating Parts

Never operate engine with covers

or guards removed. Rotating parts

can cause severe injury. Keep

hands, feet, hair, jewelry and

clothing away from all moving parts.

Page iv

I. General Safety Precautions

A. Avoid Carbon Monoxide Poisoning

All engine exhaust

contains carbon

monoxide, a deadly

gas. Breathing

carbon monoxide

can cause head-

aches, dizziness,

drowsiness,

nausea, confusion

and eventually death.

Carbon monoxide is a colorless, odorless, tasteless

gas which may be present even if you do not see or

smell any engine exhaust. Deadly levels of carbon

monoxide can collect rapidly and you can quickly be

overcome and unable to save yourself. Also, deadly

levels of carbon monoxide can linger for hours or

days in enclosed or poorly-ventilated areas. If you

experience any symptoms of carbon monoxide

poisoning, leave the area immediately, get fresh air,

and SEEK MEDICAL TREATMENT.

To prevent serious injury or death from carbon

monoxide:

• NEVER run engine indoors. Even if you try

to ventilate engine exhaust with fans or

open windows and doors, carbon monoxide

can rapidly reach dangerous levels.

• NEVER run engine in poorly-ventilated or

partially enclosed areas such as barns,

garages, basements, carports, under

dwellings, or in pits.

• NEVER run engine outdoors where engine

exhaust can be drawn into a building through

openings such as windows and doors.

B. Avoid Gasoline Fires

Gasoline (fuel) vapors are highly

flammable and can explode. Fuel

vapors can spread and be ignited by

a spark or flame many feet away from

engine. To prevent injury or death

from fuel fires, follow these instruc-

tions:

WARNING

Read equipment manufacturer’s manual

and this material thoroughly before using

this engine. Failure to do so can result in

serious injury or death. Call Tecumseh

Products Company at 1-800-558-5402 if

you have any questions.

• NEVER store engine with fuel in fuel tank

inside a building with potential sources of

ignition such as hot water and space heaters,

clothes dryers, electric motors, etc.

• NEVER remove fuel cap or add fuel when

engine is running.

• Allow engine to cool before refueling.

• NEVER fill fuel tank indoors. Fill fuel tank

outdoors in a well-ventilated area.

• DO NOT smoke while refueling tank.

• Use only an approved red GASOLINE

container to store and dispense fuel.

• DO NOT attempt to pour fuel from engine.

Empty fuel tank by running engine.

C. Transporting Engine

DO NOT transport engine with fuel in tank. Fuel vapor

or spilled fuel may ignite.

D. Avoid Other Fires

To reduce the risk of fire, keep all materials that can

burn, including grass and leaves, away from muffler

and the rest of the engine.

E. Stay Away from Hot Surfaces

The muffler and other engine parts

become extremely hot during

operation and remain hot after the

engine has stopped. To avoid

severe burns on contact, stay away

from these areas.

F. Do Not Modify Engine

To avoid serious injury or death, DO NOT modify

engine in any way. NEVER tamper with the factory

setting of engine governor. Running the engine faster

than the speed set at the factory can be dangerous and

will VOID THE ENGINE WARRANTY.

G. Avoid Accidental Starts

To prevent accidental starting when working on equip-

ment, always disconnect spark plug wire and keep it

away from spark plug.

H. Stay Away from Rotating Parts

Never operate engine with covers

or guards removed. Rotating parts

can cause severe injury. Keep

hands, feet, hair, jewelry and

clothing away from all moving parts.

Page iv

1-1695578

Tecumseh engine model, specification and serial

numbers are stamped or on a decal on the blower

housing. The decal also contains any emission compli-

ance information.

The letters which precede the model numbers indicate

the basic type of engine:

VLV - Vector Lightweight Vertical

Prior to 1999

The numbers which followed the engine type letters

indicated the basic engine horsepower:

40 - 4.0 Horsepower

50 - 5.0 Horsepower

The current designation indicates cubic inch displace-

ment

126 - 12.6 cubic inches

Following the engine model numbers are the engine

specifications numbers.

The specification number is used when identifying

engine parts. Example 502012A.

The serial or D.O.M. Number is the production date

code.

2039 - serial number (example)

2 - Year in decade of manufacture (2002)

39 - The last 3 digits of date code represent

the calendar (the 39th day of 2002)

D - represents the shift and line on which the

engine was built at the factory.

Emitted engines that meet the California Air Resource

Board (C.A.R.B.) or the Environmental Protection

Agency (E.P.A.) Standards will include additional

required engine information on the engine decal.

NOTE

To maintain best possible emission performance, use only

Genuine Tecumseh Parts.

Short Blocks

New short blocks are identified by a tag marked SBH

(Short Block Horizontal) or SBV (Short Block Vertical).

These tags are used to properly identify the correct

parts if service is required. They are attached to either

the sump bolts or valve box cover.

Chapter 1

General Information

Engine Identification

6215C

207cc

THIS ENGINE MEETS 1995-1998

CALIF. EMISSION REGULATIONS FOR

ULGE ENGINES AS APPLICABLE

FUEL: REGULAR UNLEADED OIL: USE SAE 30

VLV60-502012A

VLV60-502012A (D)

RTP358UIG2RA

6215C

1-2 695578

Parts Identification

This is a parts breakdown of a typical VLV engine. Use

this parts breakdown to identify parts. When ordering

parts always refer to the engine model and specification

number stamped on the engine blower housing.

Carburetor and starter breakdowns are found in the

chapters referring to their repair.

NOTE

If the short block has been replaced, an identification

tag for service parts is located on the valve box cover.

SBV-XXX

SER-XXX

Optional

Pre-Filter

NOTE

On newer VLV models the breather

tube will be a straight hose.

Model and Serial

Numbers Located

Here

106

1-3695578

Ref.

No. Part Name

1 Cylinder Ass'y.

2 Pin, Dowel

3 Element, Breather

4 Cover, Breather

5 Gasket, Breather cover

6 Screw, Thread forming, 10-24 x 1/2

7 Body, Breather valve

8 Valve, Breather check

9 Breather, Tube

10 Washer, Flat

11 Rod, Governor

12 Lever, Governor

13 Clamp, Governor lever

14 Screw, 8-32 x 5/16

15 Spring, Governor extension

16 Seal, Oil

17 Baffle, Blower housing (Incl. No. 195)

18 Screw, 1/4-20 x 5/8

19 Crankshaft Ass'y.

20 Piston & Pin Ass'y.

21 Ring Set, Piston

22 Ring, Piston pin retaining

23 Rod Ass'y., Connecting

24 Bolt, Connecting rod

25 Lifter, Valve

26 Camshaft Ass'y.

27 Pump Ass'y., Oil

28 Gasket, Mounting flange

29 Flange, Mounting

30 Plug, Oil drain

31 Seal, Oil

32 Washer, Flat

33 Gear Ass'y., Governor

34 Spool, Governor

35 Ring, Retaining

36 Gear, Idler

37 Screw, 1/4-20 x 1-9/16

38 Key, Flywheel

39 Flywheel

40 Fan, Flywheel

41 Washer, Belleville

42 Nut, Flywheel

43 Solid State Ass'y.

44 Cover, Spark plug

45 Screw, 10-24 x 1

46 Wire Ass'y., Ground

47 Gasket, Cylinder head

48 Head, Cylinder

49 Valve, Exhaust

50 Valve, Intake

51 Screw, 5/16-18 x 1-1/2

52 Spark Plug (Champion RJ-17LM or equivalent)

53 Spring, Valve

54 Cap, Valve spring

55 Gasket, Valve cover

56 Cover, Valve spring box

57 Screw, 10-24 x 1/2

58 Stud, Carburetor mounting

59 Link, Governor

60 Spacer, Carburetor mounting gasket

61 Lever Ass'y., Brake

62 Lever, Brake control

63 Link, Brake control lever

64 Spring, Brake

65 Ring, Retaining

66 Terminal

67 Spring, Brake control lever

68 Bushing, Brake control leer & brake lever

69 Spring, Compression

70 Spring, Compression

71 Screw, 5-40 x 7/16

72 Screw, 6-32 x 21/32

73 Gasket, Carburetor to air cleaner

74 Body, Air cleaner (Incl. Nos. 239, 299 & 350)

75 Screw, 10-32 x 2-3/32

76 Filter, Air cleaner (Paper)

77 Cover, Air cleaner

78 Nut, Lock, 1/4-20

79 Screw, 1/4-20 x 11/16

80 Plate, Control Ass'y., cover

81 Screw, 8-32 x 1/2

82 Housing, Blower

83 Screw, 1/4-20 x 1/2

84 Ring, Starter

85 Muffler

86 Plate, Muffler locking

87 Screw, 5/16-18 x 2-11/32

88 Cup, Starter

89 Screw, 8-32 x 21/64

90 Line, Fuel

91 Clamp, Fuel line

92 Clip, "U" Type Nut, 10-32

93 Tank Ass'y., Fuel

94 Cap, Fuel

95 Tube, Oil fill

96 "O" Ring

97 Clip, Fill tube

98 Dipstick, Oil

99 Plug, Starter

100 Screw, 10-32 x 35/64

101 Primer

102 Decal, Instruction

103 Decal, Primer

104 Carburetor

105 Starter, Rewind

106 Carb Fix Kit

Ref.

No. Part Name

1-4 695578

Oil and Fuel Specifications

Oil

To operate engine you need to use a clean, high quality,

detergent oil. For recommended engine oil, See Table 1.

NOTES

Be sure original container is marked A.P.I. Service

“SL/SJ”.

Using multigrade oil above 32

F (0

C) will increase oil con-

sumption. SAE10W40 is not recommended.

The oil sump capacity is 21 ounces or 1-1/4 U.S. Pints

(.62 liters). Tecumseh special-formulated oils are avail-

able at your Authorized Tecumseh Servicing Dealer.

Fuel

Use unleaded regular, unleaded premium or reformu-

lated automotive fuel only. You may use gasoline

containing the following components identified in

Table 2.

• DO NOT use leaded fuel.

• Fuel must be fresh and clean. NEVER use fuel

left over from last season or stored for long

periods.

• NEVER mix oil with fuel.

• DO NOT use fuel containing Methanol (Wood

Alcohol).

Filling Fuel Tank

Gasoline (fuel) vapors are highly

flammable and can explode. Fuel

vapors can spread and be ignited by a spark or

flame many feet away from engine. To prevent

injury or death from fuel fires, follow these

instructions:

1. Stop engine and allow it to cool before refueling.

2. Be sure engine is outdoors and in a well-ventilated

area.

3. Clean area around fuel fill cap and remove fuel fill

cap. See Figure 2.

4. Using an approved red GASOLINE container, add

fuel slowly, being careful to avoid spilling. DO NOT

overfill fuel tank. Leave space in the tank to allow

fuel to expand without overflowing.

5. Replace fuel fill cap securely and wipe up spilled

fuel before starting engine. If fuel is spilled DO NOT

start engine. Move machine away from area of

spillage. Avoid creating any source of ignition until

fuel vapors are gone.

Stopping the Engine and

Short-Term Storage

Stop engine according to equipment manufacturer’s

instructions.

Never store the engine with fuel

in the fuel tank inside a building

with potential sources of ignition

such as hot water and space heaters, clothes

dryers, electric motors, etc.

Temperature

Recommended Oil

Straight

Grade

Table 1. Recommended Engine Oil

Above 32

F (0

F to 32

F (-18

C to 0

Below 0

F (-18

C) SAE 0W30

Multi

Grade

Tecumseh Part No.

730225A

SAE30W

Tecumseh Part No.

730226A

SAE5W30

SAE10W

Oil Type

Fuel Component

Percentage

Table 2. Recommended Fuel

Ethanol

Grain Alcohol (“Gasohol”)

10%

MTBE (Methyl Tertiary Butyl Ether)

ETBE (Ethyl Tertiary Butyl Ether)

15%

WARNING



WARNING



1-5695578

Removing Debris from Engine

Before each use, remove grass clippings, dirt and debris

from the following areas:

• Cooling fins

• Air intake screen

• Levers

• Linkage

Removing debris will insure adequate cooling, correct

engine speed and reduce the risk of fire.

WARNING



WARNING



Maintenance and Adjustments

To prevent accidental starting

when working on equipment,

always disconnect spark plug wire

and keep it way from spark plug by attaching it

securely to grounding post.

The muffler and other engine

parts become extremely hot

during operation and remain hot

after the engine has stopped. To avoid severe

burns on contact, stay away from these areas.

Grounding Post

Spark Plug Wire

Spark Plug

Spark Plug / Grounding Post

Cooling Fins

Levers and Linkage

Oil Drain Plug

Muffler

Bottom of Engine

Checking and Changing Oil

To avoid engine damage, it is important to:

• Check oil level after every 5 operating hours when

engine is warm and before each use.

• Change oil after first 2 operating hours and every

25 operating hours thereafter; more often if

operated in extremely dusty or dirty conditions.

Engine should still be warm but not hot from recent

use.

1. Be sure you find the correct drain plug location if

present. (See equipment manufacturer’s instructions).

2. Disconnect spark plug wire and keep it away from

spark plug by attaching it securely to grounding post.

3. Make sure the gas cap is on and is tightened securely.

4. Clean area around oil drain plug.

5. Place approved recyclable oil container under oil drain

plug, tipping engine to position the oil drain plug at

the lowest point on the engine. (See equipment

manufacturer’s instructions).

6. Remove oil drain plug and drain oil.

7. Install oil drain plug and tighten securely.

8. Fill with recommended oil. See Table 2.

9. Wipe away any spilled oil.

1-6 695578

Spark Plug

Check spark plug yearly or every 100 operating hours.

1. Clean area around spark plug.

2. Remove and inspect spark plug.

3. Replace spark plug if porcelain is cracked or if

electrodes are:

• Pitted

• Burned

• Fouled with deposits

4. Check electrode gap with wire feeler gauge and set

gap to .030 (0.76mm) if necessary.

5. Install spark plug and tighten securely.

NOTE

A resistor spark plug must be used for replacement

(Tecumseh part no. 33636, or Champion part no. RJ-17LM).

Cleaning/Replacing Air Cleaner

Your engine has an air cleaner which helps prevent

premature engine wear and failure. NEVER run engine

without complete air cleaner installed on engine. Your

air cleaner periodically needs to be replaced.

Servicing Paper Filters

Paper filters cannot be cleaned and must be replaced

once a year or every 100 operating hours; more often if

used in extremely dusty conditions. Replacement

filters are available at a Authorized Tecumseh Servicing

Dealer. Follow the instructions next to the drawing of

your air cleaner to remove and replace it.

NOTE

DO NOT put oil on or clean paper filter.

Air Cleaner Assembly

Tabs

Cover

Flange

Slot

Paper Filter

Resistor Spark Plug

.030 (0.76mm) Gap

Electrodes

Porcelain

Carburetor

If you think your carburetor needs adjusting, see your

nearest Authorized Tecumseh Servicing Dealer. Engine

performance should not be affected at altitudes up to

7,000 feet (2,134 meters). For operation at higher

elevations, contact your Authorized Tecumseh Servicing

Dealer.

Engine Speed

To avoid serious injury NEVER

tamper with the factory setting of

engine governor. Running the

engine faster than the speed set at the factory

can be dangerous and will viod the engine

warranty.

Engine Stopping Mechanism

Some engines are equipped with

a federally-mandated mechanism

which stops the engine and mower blade. To

avoid serious injury or death as a result of

contact with the mower blade, do not interfere

with or bypass this mechanism. Parts of the

mechanism may be subject to wear and must be

checked once a year by an Authorized Tecumseh

Servicing Dealer. In the event the mechanism

fails for any reason, you must not use the engine

until corrected by an Authorized Tecumseh

Servicing Dealer.

WARNING



WARNING



1-7695578

Seasonal Storage

If engine is to be unused for more than a month, prepare

engine as indicated below:

Fuel System

Fuel stored in the tank will gradually deteriorate, leaving

gum deposits which will clog the carburetor or fuel

system. To avoid these problems, treat the fuel system

in one of the two following methods:

Method 1

NOTE

Tecumseh recommends using

ULUL

TRATRA

TRA

FRESH™FRESH™

FRESH™ gaso-

line stabilizer as an acceptable method of minimizing

formation of fuel gum deposits during storage; This prod-

uct is available from your Authorized Tecumseh Servic-

ing Dealer.

1. Add fuel preservative/stabilizer according to

manufacturers instructions.

2. Run engine at least 10 minutes after adding

stabilizer to allow it to reach carburetors.

NOTES

Always follow mix ratio found on stabilizer container.

Failure to do so may result in equipment damage.

DO NOT drain stabilizer from carburetor. Doing so may

result in gum deposits and/or corrosion and cause

equipment malfunction.

Instead of using a fuel preservative/stabilizer, you can

empty the fuel tank as follows:

Method 2

1. To prevent serious injury from fuel fires, empty fuel

tank by running engine until it stops from lack of

fuel. DO NOT attempt to pour fuel from engine.

2. Drain remaining fuel from carburetor by pressing up

on bowl drain if present.

Oil

Change oil if not changed within the last 3 months. See

“Checking and Changing Oil” instructions under “Mainte-

nance and Adjustments”.

Lubricating Cylinder Bore

When lubricating cylinder bore,

fuel may spray from the spark

plug hole. To prevent serious injury from fuel

fires, follow these instructions:

1. Disconnect spark plug wire and keep it away from

spark plug by attaching it securely to grounding

post.

2. Remove spark plug.

3. Squirt 1oz. (30ml) of clean engine oil into spark

plug hole.

4. Cover spark plug hole with rag to prevent fuel from

spraying from spark plug hole when starter rope is

pulled.

5. Grasp starter cord handle and pull out slowly using

a full arm stroke. Repeat once. (This will distribute

oil throughout the cylinder to prevent corrosion

during storage.)

6. Install spark plug.

NOTE

Connect spark plug wire before attempting to start en-

gine once engine is out of storage.

Quick Maintenance Chart

Every 200 hours/seasonally

Every 100 hours/seasonally

Check oil level

Change oil

Clean foam filter

Replace paper filter

Check spark plugs

Replace spark plug

PROCEDURE:

After first two hours

Every 5 hours or daily

Every 25 hours/3 months

•

WARNING



1-8 695578

Tecumseh four-cycle engines require four strokes or cycles

to complete one power cycle.

Intake

Intake valve is open, exhaust valve is closed. Piston is

traveling downward creating a suction action, drawing the

fuel-air mixture from the carburetor into the cylinder area

above the piston.

Compression

As the piston reaches Bottom Dead Center, the IN-

TAKE valve closes. The piston then rises, compressing

the fuel and air mixture trapped in the combustion

chamber, because both valves are closed.

NOTE

Some emission compliance engines may use an RCR

(Ramp Compression Relief) system. This system opens

the intake valve during the compression stroke allowing

a small amount of the intake charge back down the in-

take pipe. This eliminates unburned fuel going out the

exhaust during normal compression relief cycle typically

used on the exhaust valve.

1. Intake

2. Compression

Power

Both valves remain closed. As the piston reaches the

Before Top Dead Center (BTDC) ignition point, the spark

plug fires, igniting the fuel-air mixture. In the time it

takes to ignite all the available fuel, the piston has

moved to TDC (Top Dead Center), ready to take the full

combustive force of the fuel for maximum power and

piston downward travel. The expanding gases force the

piston down.

Exhaust

Exhaust valve opens. As the piston starts to the top of

the cylinder, the exhaust gases are forced out.

After the piston reaches Top Dead Center (TDC), the

four cycle process will begin again as the piston moves

downward and the intake valve opens.

3. Power

4. Exhaust

4-Cycle Engine Theory

2-1695578

Chapter 2

Air Cleaners

General Information

It is recommended that you take

special notice of all items

discussed in the handbook and wear the

appropriate safety equipment. Failure to do so

may result in death or serious injury.

Be sure dirt and debris

surrounding air cleaner is

removed before servicing. Failure to do so may

result in carburetor and/or engine damage.

NOTE

If the engine is equipped with an optional poly pre-filter

always remove it first, to prevent dirt falling into the filter

body.

Air cleaners must be serviced frequently, to prevent dust

and dirt from entering the engine. Dust mixed with the

engine oil forms an extremely abrasive compound which

quickly wears out an engine.

A clogged air cleaner will affect engine performance.

Replacing a restricted (clogged) air filter should restore

engine performance.

Air Cleaner Service

The engine utilizes a treated paper element with a foam

rubber-like sealing edge. The seal must fit properly to

prevent dirt ingestion.

Replace air filter once a year or more often in extremely

dusty or dirty conditions.

NOTE

Do not put oil on or clean a paper filter.

Be sure to clean base and cover thoroughly before

installing new paper filter.

DO NOT run engine without

complete air cleaner installed on

engine. Doing so may result in equipment

damage and WILL VOID the engine WARRANTY.

NOTE

Serious damage to the engine may result from using any

other but the specified part number filter. Use factory

recommended parts only.

Some models use a dual stage air cleaner. This air

cleaner uses a polyurethane-type foam pre-filter along

with the paper element.

Polyurethane Pre-Filters

These serviceable air filters utilize a polyurethane

element which will clog up with use. The element

should be cleaned and serviced in the following manner.

1. Wash element in a detergent and water solution

and squeeze (don’t twist) until all dirt is removed.

2. Rinse thoroughly.

3. Wrap in a clean cloth and squeeze (don’t twist)

until completely dry.

4. Re-oil element by applying a generous quantity of

oil to all sides. Squeeze vigorously to distribute oil

and to remove excess oil.

5. Clean air cleaner housing and cover.

Dry thoroughly.

6. Reinstall pre-cleaner in air filter body.

NOTE

Some vectors Are

equipped with a bolt

access hole and a plug.

Replace if removed.

Body

Paper

Filter

Plug

Poly

Pre-Filter

WARNING

CAUTION

2-2 695578

To Service Air Cleaner

1. Loosen cover screw (A).

7. Clean and install pre-filter (if so equipped).

8. Reinstall cover to air cleaner body.

Be sure hinge is assembled properly.

9. Swing cover up and tighten cover screw.

(Do not over tighten).

2. Swing cover down and remove from hinge (B).

3. Pull foam pre-filter out of air cleaner body

(if equipped with pre-filter).

4. Pull air filter out of air cleaner body.

5. Clean air cleaner cover and body.

6. Install a new paper filter (part no. 36046) (C).

Pre-Filter

2-3695578

Carburetion

Split

Ref.

No. Part Name

1 Throttle Shaft & Lever Ass'y.

5 Dust Seal (Throttle)

6 Throttle Shutter

7 Throttle Shutter Screw

25 Float Bowl

25A Idle Restrictor

26 Float

27 Shaft, Float

29 Gasket, Float Bowl to Body

30 Inlet Needle, Seat & Seat Retainer (Incl. 31)

31 Seat Retainer

32 Bowl Drain Ass'y.

36 Tube, Main Nozzle

37 O Ring, Main Nozzle Tube

38 Spring, Main Nozzle Tube

39 Float Bowl Retainer

47 Welch Plug, Idle Mixture Well

Married

38A

37A

25A

Ref.

No. Part Name

1 Throttle Shaft & Lever Ass'y.

5 Dust Seal

6 Throttle Shutter

7 Throttle Shutter Screw

25 Float Bowl

25A Idle Restrictor

26 Float

27 Float Shaft

29 Gasket, Float Bowl to Body

30 Inlet Needle, Seat & Seat Retainer (Incl. 31)

31 Seat Retainer

32 Bowl Drain Screw

33 Bowl Drain Washer

36 Tube, Main Nozzle

37 O Ring, Main Nozzle Tube

37A O Ring

38 Spring, Main Nozzle Tube

38A Spring

39 Float Bowl Retainer

40 Main Fuel Jet

47 Welch Plug, Idle Mixture Well

25A

General

Proper Carburetion Function is dependent on clean

fresh fuel and a well maintained air cleaner system.

Most causes of carburetion problems are directly

related to stale fuel and dirt ingestion. Inspection of the

carburetor for dirt wear and fuel deposits should always

be done before servicing the carburetor.

Carburetor Identification

Tecumseh carburetors are identified by a manufacturing

number and date code stamped on the carburetor as

shown. When servicing carburetors, use the engine

model number or the manufacturing number on the

carburetor to find repair parts in the Master Parts

Manual.

The engine has used both a split system and married

system carburetor. Below are the part breakdowns for

the two carburetors.

TORX E-5

Stud

NOTE

Later model vector carburetor bodies are held on with

TORX E-5 Studs. You will need this socket for removal.

Use Tecumseh Part No. 670339.

*NOTE: The seat retainer may not be present on some engines. If you receive a retainer as a service part, install it.

Manufacturing Number

and Date Code

2-4 695578

The carburetor is a float feed, nonadjustable type, with a

one piece extruded aluminum body. The float bowl,

float, nozzle, and venturi are nonmetallic, minimizing the

corrosion and varnishing problems.

Gasoline (fuel) vapors are highly

flammable and can explode. Fuel

vapors can spread and be ignited by a spark or

flame many feet away from engine. To prevent

injury or death from fuel fires, follow these

instructions:

• NEVER fill fuel tank indoors. Fill fuel tank

outdoors in a well-ventilated area.

• Use only an approved red GASOLINE container

to store and dispense fuel.

• If fuel is spilled, DO NOT start engine. Move

machine away from area of spillage. Avoid

creating any source of ignition until fuel vapors

are gone.

Common service areas of the carburetor are contained

in the fuel bowl. These areas are the float, needle, seat

and main nozzle. All of these parts can be serviced

without removing the carburetor body from the engine.

NOTE

Be sure to check the cross holes on the body of the

nozzle and the main orifice in the bottom of the nozzle.

Compressed air can pierce the

skin and cause injury. DO Not use

your hand to check for leaks or to determine air

flow rates. Wear safety glasses to shield from

debris. Failure to do so could result in death or

serious injury.

7. Use a rubber tipped tapered nozzle on air hose and

apply low pressure compressed air or use a

monofilament fishing line to remove any deposits

in the main jet or cross holes.

Float Bowl Service

1. Be sure engine is outdoors and in a well-ventilated

area.

2. Disconnect and plug the fuel line.

3. Remove the bowl drain screw.

4. Remove the float bowl by snapping the bale spring

towards the throttle end of the carburetor.

NOTE

Use care when using tools to remove the bail from the

carburetor. Failure to do so may result in bending the

retainer.

After the bowl gasket is removed, the parts contained in

the bowl can be inspected and serviced.

5. Pull out the main nozzle and spring.

6. Inspect the main nozzle for deposits.

WARNING



WARNING



Married System Main Jet

Split System Main Jet

Jet and Nozzle Ass'y.

"O" Ring

Air

Bleed

Holes

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Tecumseh VLV Technician's Handbook

Brand: Tecumseh

Model: VLV

Category: Engine

Type: Technician's Handbook

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Tecumseh VLV Technician's Handbook

Tecumseh VLV Technician's Handbook

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