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 |

#41

Auger housing assembly diagram

Lock nut

Part #90008287

Replaced by #703232

This item is not returnable

$6.24 |

14% OFF Phone Price : $7.24

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#30

Motor mount assembly diagram

V-belt

Part #90003526

Replaced by #3526MA

Get free shipping with Automatic Reorder

$27.49 |

18% OFF Phone Price : $33.49

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#16

Upper handle assembly diagram

Bolt

Part #90070985

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

Bolt

Part #90070993

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

Gear box diagram

Worm gear

Part #90053730

Replaced by #1752500YP

$89.24 |

6% OFF Phone Price : $95.24

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Gear box diagram

Seal

Part #90053744

Replaced by #780151MA

This item is not returnable

$15.92 |

11% OFF Phone Price : $17.92

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#24

Auger housing assembly diagram

Bearing

Part #90085087

Replaced by #761508MA

$84.39 |

7% OFF Phone Price : $90.39

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#21

Auger housing assembly diagram

Screw

Part #90000130

Replaced by #577400MA

This item is not returnable

$8.09 |

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#22

Upper handle assembly diagram

Cap retrainr

Part #90073664

Replaced by #73664MA

This item is not returnable

$8.49 |

11% OFF Phone Price : $9.49

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#17

Auger housing assembly diagram

Bolt

Part #90071147

Replaced by #578088MA

This item is not returnable

$8.69

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Symptoms for gas snowblowers

Choose a symptom to see related snowblower repairs.

View all

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 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…

Why does my snowblower stop running after a few seconds?

Main causes: dirty carburetor, stale fuel…

What should I do about a damaged snowblower tire?

Main causes: punctured tire, damaged rim…

Why does my snowblower engine run rough?

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

Why won't my snowblower start?

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

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…

Why won't my snowblower chute turn?

Main causes: snow build-up in chute, chute drive mechanism failure, bad chute control assembly…

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, …

Repair guides for gas snowblowers

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

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How to adjust snowblower engine valve lash

Adjust the engine valve lash on your snowblower to keep the engine starting and running smoothly.…

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 replace a snowblower shave plate

Follow the 7 easy steps in this repair guide/video to replace a worn out shave plate on your snowblower.…

Repair difficulty

Time required

15 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

How do I tune up my snowblower?

Why won't my snowblower throw snow far enough?

Why does my snowblower stop running after a few seconds?

What should I do about a damaged snowblower tire?

Why does my snowblower engine run rough?

Why won't my snowblower start?

Why doesn't my snowblower self propel?

Why won't my snowblower chute turn?

Why won't my snowblower clear snow well?

Repair guides for gas snowblowers

How to adjust snowblower engine valve lash

How to adjust snowblower skid shoes

How to replace a snowblower shave plate

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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