Troybilt
Gas Walk-Behind Mower

Model # S979 Official Troybilt lawn mower

Here are the diagrams and repair parts for Official Troybilt S979 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 154 parts  |

Blade-21" Mu 742-0741
#85

Handle/deck/wheels diagram

Blade-21" mu

Part #742-0741

Replaced by #942-0741A

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Manufacturer substitution
This part replaces 742-0741. Substitute parts can look different from the original.
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$27.71
18% OFF Phone Price : $33.71
In Stock
Knob Wing Nut 720-0284
#17

Handle/deck/wheels diagram

Knob wing nut

Part #720-0284

Replaced by #720-04072A

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Manufacturer substitution
This part replaces 720-0284. Substitute parts can look different from the original.
BEST SELLER
$9.33
10% OFF Phone Price : $10.33
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Wing Nut 712-0397
#33

Handle/deck/wheels diagram

Wing nut

Part #712-0397

Replaced by #712-0397A

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Manufacturer substitution
This part replaces 712-0397. Substitute parts can look different from the original.
This item is not returnable
$5.22
16% OFF Phone Price : $6.22
In Stock
Lawn & Garden Equipment Hex Cap Screw 710-0751
Lawn & garden equipment hex cap screw

Part #710-0751

This item is not returnable
$5.12
16% OFF Phone Price : $6.12
In Stock
Lawn & Garden Equipment Carriage Bolt (replaces 1186069, 583108, 706-101080, 706-10602-12, 791-182213) 710-0703
Lawn & garden equipment carriage bolt (replaces 1186069, 583108, 706-101080, 706-10602-12, 791-182213)

Part #710-0703

This item is not returnable
$6.46
13% OFF Phone Price : $7.46
In Stock
Toro Lawn & Garden Equipment Flat Washer 736-3084
#32

Rear axle/bag/housing/shaft diagram

Toro lawn & garden equipment flat washer

Part #736-3084

This item is not returnable
$6.14
14% OFF Phone Price : $7.14
In Stock
Complete Wheel 734-2004A
#60

Handle/deck/wheels diagram

Complete wheel

Part #734-2004A

Replaced by #753-08093

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Manufacturer substitution
This part replaces 734-2004A. Substitute parts can look different from the original.
$47.45
11% OFF Phone Price : $53.45
In Stock
Sears Lawn Mower Roller Wheel 756-0625
#43

Handle/deck/wheels diagram

Sears lawn mower roller wheel

Part #756-0625

This item is not returnable
$12.00
14% OFF Phone Price : $14.00
In Stock
Ryobi Lawn & Garden Equipment Flat Washer 736-0204
#66

Handle/deck/wheels diagram

Ryobi lawn & garden equipment flat washer

Part #736-0204

This item is not returnable
$5.43
16% OFF Phone Price : $6.43
In Stock
Cable Tie 726-0240
#20

Handle/deck/wheels diagram

Cable tie

Part #726-0240

Replaced by #726-0178

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Manufacturer substitution
This part replaces 726-0240. Substitute parts can look different from the original.
This item is not returnable
In Stock

Symptoms for gas walk-behind mowers

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

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

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

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

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

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

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

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.

How to replace a lawn mower spark plug

How to replace a lawn mower spark plug

Take a few minutes to replace the spark plug during your lawn mower's annual tune-up or if the spark plug is burnt or cr…

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

How to replace a lawn mower blade

Check your lawn mower blade regularly and replaced it if it's bent or damaged. …

Repair difficulty
Time required
 15 minutes or less
How to replace a lawn mower flywheel key on a flathead engine

How to replace a lawn mower flywheel key on a flathead engine

When you hit a hard object with your mower, the flywheel can shear to protect more expensive components. Learn how to re…

Repair difficulty
Time required
 45 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

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

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

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

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Top questions about Sears and Sears PartsDirect

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