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MTD
Gas Walk-Behind Mower

Model # 12A-26MB055 Official MTD lawn mower

Here are the diagrams and repair parts for Official MTD 12A-26MB055 lawn mower, as well as links to manuals and error code tables, if available.

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Owner’s manual
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Model diagram and schematic

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ALL PARTS
Showing 10 of 37 parts  |
Yard Machines Lawn & Garden Equipment Cupped Washer 736-0270
#49

Lawn mower diagram

Yard machines lawn & garden equipment cupped washer

Part #736-0270

This item is not returnable
$5.10 | 
16% OFF Phone Price : $6.10
In Stock
Lawn Mower Height Adjuster Lever (replaces 687-02051) 732-1026
#60

Lawn mower diagram

Lawn mower height adjuster lever (replaces 687-02051)

Part #732-1026

This item is not returnable
$10.14 | 
16% OFF Phone Price : $12.14
In Stock
Lawn Mower Drive Control Bar 747-1214
#1

Lawn mower diagram

Lawn mower drive control bar

Part #747-1214

This item is not returnable
$31.02 | 
16% OFF Phone Price : $37.02
In Stock
Lawn & Garden Equipment Shoulder Screw 738-1173
#55

Lawn mower diagram

Lawn & garden equipment shoulder screw

Part #738-1173

$11.63
In Stock
Bearing Spacer 748-0390
#59

Lawn mower diagram

Bearing spacer

Part #748-0390

$9.69
In Stock
Lawn Mower Extension Spring 732-04049
#44

Lawn mower diagram

Lawn mower extension spring

Part #732-04049

This item is not returnable
$6.63
In Stock
Yard Machines Lawn & Garden Equipment Wing Nut (replaces 01002925, 920-0279) 720-0279
#7

Lawn mower diagram

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
Deck Asm-22" 687-02046
#22

Lawn mower diagram

Deck asm-22"

Part #687-02046

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

Height Plate 782-0584
#36

Lawn mower diagram

Height plate

Part #782-0584

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

Clip 17098
#15

Lawn mower diagram

Clip

Part #17098

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.…

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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