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Craftsman
Gas Walk-Behind Mower

Model # 917378451 Official Craftsman gas walk-behind lawn mower

Here are the diagrams and repair parts for Official Craftsman 917378451 gas walk-behind lawn mower, as well as links to manuals and error code tables, if available.

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  • In the search box below, enter all or part of the part number or the part’s name.

Not all parts are shown on the diagrams—those parts are labeled NI, for “not illustrated”.

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Owner’s manual
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Model diagram and schematic

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ALL PARTS
Showing 10 of 138 parts  |
Gear Case Kit 183404

#NI

All parts diagram

Gear case kit

Part #183404

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

High Pro Key 87677
#23

Engine/handle/housing diagram

High pro key

Part #87677

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

Lawn Mower Selector Spring 175053X004
#32

Engine/handle/housing diagram

Lawn mower selector spring

Part #175053X004

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

Lawn Mower Discharge Chute Door Spring, Left 180071
#16

Engine/handle/housing diagram

Lawn mower discharge chute door spring, left

Part #180071

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

Lawn & Garden Equipment Engine Oil, 20-oz 33000

#(NI)

All parts diagram

Lawn & garden equipment engine oil, 20-oz

Part #33000

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

Lawn Mower Height Adjuster 151520
#41

Wheels/tires/bag diagram

Lawn mower height adjuster

Part #151520

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

Lawn & Garden Equipment Pan Head Screw 158755
#4

Wheels/tires/bag diagram

Lawn & garden equipment pan head screw

Part #158755

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

Lock Washer 850263
#49

Engine/handle/housing diagram

Lock washer

Part #850263

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

Upper Handle 183485
#1

Engine/handle/housing diagram

Upper handle

Part #183485

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

Assembly 175576X479
#14

Engine/handle/housing diagram

Assembly

Part #175576X479

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

Symptoms for gas walk-behind mowers

Choose a symptom to see related walk-behind mower repairs.

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Why does my lawn mower vibrate a lot?

Main causes: damaged cutting blade, loose cutting blade, damaged flywheel key, engine needs tune up…

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Why does my lawn mower cut unevenly?

Main causes: uneven wheel height settings, damaged wheel, dull or damaged cutting blade…

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Why does my lawn mower run rough?

Main causes: engine needs tune up, dirty or clogged carburetor, damaged flywheel key…

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Why won't my lawn mower move?

Main causes: drive control cable failure, worn or broken drive belt, bad transmission, broken drive wheel…

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Why won't my lawn mower start?

Main causes: stale gas, engine needs tune up, bad spark plug, dead battery, bad recoil starter, faulty safety switch, ba…

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Why does my lawn mower stall?

Main causes: dirty carburetor, bad spark plug, clogged air filter, engine choke problems, clogged gas cap vent…

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Repair guides for gas walk-behind mowers

These step-by-step repair guides will help you safely fix what’s broken on your walk-behind lawn mower.

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How to rebuild a lawn mower carburetor

How to rebuild a lawn mower carburetor

The carburetor mixes air with fuel to drive the piston. Rebuild the carburetor if it's clogged or leaks.…

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Repair difficulty
Time required
 60 minutes or less
How to replace a lawn mower recoil starter on an OHV engine

How to replace a lawn mower recoil starter on an OHV engine

Replace the recoil starter if it doesn't move when you pull the starter rope.…

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Repair difficulty
Time required
 15 minutes or less
How to replace a lawn mower wheel

How to replace a lawn mower wheel

Learn how replace a damaged wheel on a walk-behind lawn mower—it's a quick, easy fix.…

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Repair difficulty
Time required
 15 minutes or less

Effective articles & videos to help repair your walk-behind mowers

Use the advice and tips in these articles and videos to get the most out of your walk-behind lawn mower.

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How to enjoy all the online benefits we offer on our Sears PartsDirect website

How to enjoy all the online benefits we offer on our Sears PartsDirect website

Learn about all the convenient features on our Sears PartsDirect website that make your parts purchases easier.…

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Top questions about Sears and Sears PartsDirect

Top questions about Sears and Sears PartsDirect

Get answers to frequently asked questions about Sears and Sears PartsDirect.…

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Types of walk-behind mower blades video

Types of walk-behind mower blades video

Learn about the different kinds of mower blades and how to maintain them.…

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