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MTD
Gas Walk-Behind Mower

Model # 12A-979L401 Official MTD gas lawn mower

Here are the diagrams and repair parts for Official MTD 12A-979L401 gas 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.

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Owner’s manual

Model diagram and schematic

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ALL PARTS
Showing 10 of 192 parts  |
Bell Support 736-0524A
#69

Transaxle assembly diagram

Bell support

Part #736-0524A

Replaced by #736-0524B-1

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Manufacturer substitution
This part replaces 736-0524A. Substitute parts can look different from the original.
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$6.58 | 
13% OFF Phone Price : $7.58
In Stock
Ball Bearing 741-0600
#7

Transmission diagram

Ball bearing

Part #741-0600

Replaced by #941-0600

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Manufacturer substitution
This part replaces 741-0600. Substitute parts can look different from the original.
BEST SELLER
$28.71 | 
17% OFF Phone Price : $34.71
In Stock
Aircap Lawn Tractor Screw (replaces 150011, 910-0134) 710-0134
#1

Transaxle assembly diagram

Aircap lawn tractor screw (replaces 150011, 910-0134)

Part #710-0134

This item is not returnable
$6.55 | 
13% OFF Phone Price : $7.55
In Stock
Yard Machines Lawn & Garden Equipment Wing Nut (replaces 01002925, 920-0279) 720-0279
Yard machines lawn & garden equipment wing nut (replaces 01002925, 920-0279)

Part #720-0279

This item is not returnable
$6.87 | 
13% OFF Phone Price : $7.87
In Stock
Sears Lawn & Garden Equipment Plastic Plug 721-0325
#25

Transmission diagram

Sears lawn & garden equipment plastic plug

Part #721-0325

This item is not returnable
$6.75 | 
13% OFF Phone Price : $7.75
In Stock
Yard Machines Lawn & Garden Equipment Guide Bolt 710-1205
#7

Handles 959/979 diagram

Yard machines lawn & garden equipment guide bolt

Part #710-1205

This item is not returnable
$5.01 | 
17% OFF Phone Price : $6.01
In Stock
Hex Nut 712-0267
#38

Handles e979 diagram

Hex nut

Part #712-0267

Replaced by #712-3010

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Manufacturer substitution
This part replaces 712-0267. Substitute parts can look different from the original.
$7.71
In Stock
V-belt 754-0460
#66

Transaxle assembly diagram

V-belt

Part #754-0460

Replaced by #954-0460

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Manufacturer substitution
This part replaces 754-0460. Substitute parts can look different from the original.
This item is not returnable

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$23.49 | 
20% OFF Phone Price : $29.49
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Lawn & Garden Equipment Hex Bolt (replaces 01000943, 910-1257) 710-1257
#70

Transaxle assembly diagram

Lawn & garden equipment hex bolt (replaces 01000943, 910-1257)

Part #710-1257

This item is not returnable
$9.85 | 
9% OFF Phone Price : $10.85
In Stock
Sears Lawn & Garden Equipment Cotter Pin (replaces 914-0474) 714-0474
#21

Transaxle assembly diagram

Sears lawn & garden equipment cotter pin (replaces 914-0474)

Part #714-0474

$8.09
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 run rough?

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

Read more

Why does my lawn mower cut unevenly?

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

Read more

Why does my lawn mower vibrate a lot?

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

Read more

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…

Read more

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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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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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 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…

Read more
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. …

Read more
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…

Read more
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.…

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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

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

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