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Craftsman
Gas Walk-Behind Mower

Model # 917378721 Official Craftsman gas walk-behind lawn mower

Here are the diagrams and repair parts for Official Craftsman 917378721 gas walk-behind lawn mower, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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ALL PARTS
Showing 10 of 117 parts  |
Lock Nut 83923
#31

Main frame diagram

Lock nut

Part #83923

Replaced by #532409149

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Manufacturer substitution
This part replaces 83923. Substitute parts can look different from the original.
BEST SELLER
This item is not returnable
$5.31 | 
16% OFF Phone Price : $6.31
In Stock
Lock Nut 751592
#43

Main frame diagram

Lock nut

Part #751592

Replaced by #596322601

?
Manufacturer substitution
This part replaces 751592. Substitute parts can look different from the original.
BEST SELLER
This item is not returnable
$5.11
In Stock
Washer 52160
#12

Drive assembly diagram

Washer

Part #52160

Replaced by #596040101

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Manufacturer substitution
This part replaces 52160. Substitute parts can look different from the original.
This item is not returnable
$5.11
In Stock
Spacer 84920
#39

Main frame diagram

Spacer

Part #84920

Replaced by #532401629

?
Manufacturer substitution
This part replaces 84920. Substitute parts can look different from the original.
This item is not returnable
$5.31 | 
16% OFF Phone Price : $6.31
In Stock
Shoulder Bolt 84921
#34

Main frame diagram

Shoulder bolt

Part #84921

Replaced by #532174719

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Manufacturer substitution
This part replaces 84921. Substitute parts can look different from the original.
This item is not returnable
$13.69
In Stock
Screw 55187
#71

Main frame diagram

Screw

Part #55187

Replaced by #532428867

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Manufacturer substitution
This part replaces 55187. Substitute parts can look different from the original.
This item is not returnable
$6.64 | 
13% OFF Phone Price : $7.64
In Stock
Washer 59289
#47

Main frame diagram

Washer

Part #59289

Replaced by #532059289

?
Manufacturer substitution
This part replaces 59289. Substitute parts can look different from the original.
This item is not returnable
$6.83
In Stock
Walk-behind Lawn Mower Handle Knob 87692
#12

Main frame diagram

Walk-behind lawn mower handle knob

Part #87692

Replaced by #532087692

?
Manufacturer substitution
This part replaces 87692. Substitute parts can look different from the original.
$15.40
In Stock
Tapping Screw 750097
Tapping screw

Part #750097

Replaced by #817021008

?
Manufacturer substitution
This part replaces 750097. Substitute parts can look different from the original.
This item is not returnable
$3.99
In Stock
Lawn Mower Bushing 86960
#13

Drive assembly diagram

Lawn mower bushing

Part #86960

Replaced by #532086960

?
Manufacturer substitution
This part replaces 86960. Substitute parts can look different from the original.
This item is not returnable
$8.54
In Stock

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.…

Read more
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.…

Read more
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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