Model # 421 Official Western Tool snow blower

Here are the diagrams and repair parts for Official Western Tool 421 snow blower, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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Showing 10 of 137 parts |

#19

Upper handle assembly diagram

Spring

Part #90001673

Replaced by #1673MA

$12.31 |

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#34

Auger housing assembly diagram

Snowblower shear bolt

Part #90070971

Replaced by #1501216MA

This item is not returnable

$6.42 |

13% OFF Phone Price : $7.42

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#36

Auger housing assembly diagram

Spacer

Part #90003943

Replaced by #1501216MA

This item is not returnable

$6.42 |

13% OFF Phone Price : $7.42

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#17

Upper handle assembly diagram

Lock nut

Part #90071035

Replaced by #703251

$8.07 |

11% OFF Phone Price : $9.07

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#25

Auger housing assembly diagram

Bolt

Part #90070983

The manufacturer no longer makes this part, and there's no substitute part

#30

Motor mount assembly diagram

V-belt

Part #90003526

Replaced by #3526MA

Get free shipping with Automatic Reorder

$27.49 |

15% OFF Phone Price : $32.49

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#18

Auger housing assembly diagram

Nylock nut

Part #90071038

The manufacturer no longer makes this part, and there's no substitute part

Gear box diagram

Worm gear

Part #90053730

Replaced by #1752500YP

$94.94 |

5% OFF Phone Price : $99.94

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Gear box diagram

Gasket

Part #90000897

Replaced by #897MA

This item is not returnable

$22.85 |

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#23

Motor mount assembly diagram

Washer

Part #90073840

Replaced by #712120MA

This item is not returnable

$8.49 |

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Symptoms for gas snowblowers

Choose a symptom to see related snowblower repairs.

View all

Why doesn't my snowblower auger turn?

Main causes: broken shear pins, worn or loose auger drive belt, auger drive cable failure, damaged auger, bad gear case…

Why won't my snowblower clear snow well?

Main causes: clogged chute, snow build-up in auger housing, broken auger shear pins, auger drive belt needs adjustment, …

Why won't my snowblower start?

Main causes: stale gas, clogged carburetor, clogged or broken fuel line, dirty spark plug, bad rewind starter, incorrect…

What should I do about a damaged snowblower tire?

Main causes: punctured tire, damaged rim…

Why won't my snowblower throw snow far enough?

Main causes: clogged chute, damaged auger blades, broken shear pins, worn auger belt, damaged gear case, engine problems…

How do I tune up my snowblower?

Things to do: replace the spark plug, change the oil, rebuild the carburetor, adjust valve lash, adjust or replace the b…

Why does my snowblower engine run rough?

Main causes: dirty carburetor, clogged fuel filter, dirty spark plug, incorrect valve lash, leaky engine gaskets…

Why does my snowblower stop running after a few seconds?

Main causes: dirty carburetor, stale fuel…

Why doesn't my snowblower self propel?

Main causes: loose drive clutch cable, damaged drive clutch cable, worn friction disc, scraper blade scraping the ground…

Repair guides for gas snowblowers

These step-by-step repair guides will help you safely fix what’s broken on your snowblower.

View all

How to replace a snowblower fuel filter

Replace the fuel filter on your snowblower if it's clogged or damaged.…

Repair difficulty

Time required

15 minutes or less

How to adjust snowblower skid shoes

To prevent snowblower auger and shave plate damage, adjust the skid shoes regularly to keep the shave plate ¼-inch high.…

Repair difficulty

Time required

15 minutes or less

How to rebuild a snowblower carburetor

Rebuild the carburetor on your snowblower if the engine isn't getting fuel.…

Repair difficulty

Time required

45 minutes or less

Effective articles & videos to help repair your snowblowers

Use the advice and tips in these articles and videos to get the most out of your snowblower.

View all

How to make your snowblower last longer

Learn the steps to take to adjust and maintain your snowblower so it lasts longer.…

Introducing new technical repair content that we’re developing for the Sears Technical Institute

Learn about Sears Technical Institute and the advanced technical content being developed for aspiring appliance techs.…

Top questions about Sears and Sears PartsDirect

Model # 421 Official Western Tool snow blower

Model diagram and schematic

SEARCH WITHIN THIS MODEL

Symptoms for gas snowblowers

Why doesn't my snowblower auger turn?

Why won't my snowblower clear snow well?

Why won't my snowblower start?

What should I do about a damaged snowblower tire?

Why won't my snowblower throw snow far enough?

How do I tune up my snowblower?

Why does my snowblower engine run rough?

Why does my snowblower stop running after a few seconds?

Why doesn't my snowblower self propel?

Repair guides for gas snowblowers

How to replace a snowblower fuel filter

How to adjust snowblower skid shoes

How to rebuild a snowblower carburetor

Effective articles & videos to help repair your snowblowers

How to make your snowblower last longer

Introducing new technical repair content that we’re developing for the Sears Technical Institute

Top questions about Sears and Sears PartsDirect

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