Yard-Man
Gas Walk-Behind Mower

Model # 12A-978Q701 Official Yard-Man lawn mower

Here are the diagrams and repair parts for Official Yard-Man 12A-978Q701 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 158 parts  |

Blade-21" Mu 742-0741
#85

Handle/chute/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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$29.10
17% OFF Phone Price : $35.10
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Knob Wing Nut 720-0284
#17

Handle/chute/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
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Lawn Tractor Screw, 1/4-20 X 5/8-in (replaces 910-1652) 710-1652
Lawn tractor screw, 1/4-20 x 5/8-in (replaces 910-1652)

Part #710-1652

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This item is not returnable
$5.44
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Wing Nut 712-0397
#33

Handle/chute/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
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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
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Sears Lawn Mower Roller Wheel 756-0625
#43

Handle/chute/wheels diagram

Sears lawn mower roller wheel

Part #756-0625

This item is not returnable
$12.00
14% OFF Phone Price : $14.00
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Complete Wheel 734-2004A
#60

Handle/chute/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.
$46.07
12% OFF Phone Price : $52.07
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Toro Lawn & Garden Equipment Flat Washer 736-3084
#32

Drive control/grass bag diagram

Toro lawn & garden equipment flat washer

Part #736-3084

This item is not returnable
$6.14
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Cable Tie 726-0240
#20

Handle/chute/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
Lawn & Garden Equipment Cable Tie 725-0157
#96

Handle/chute/wheels diagram

Lawn & garden equipment cable tie

Part #725-0157

Replaced by #726-0178

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Manufacturer substitution
This part replaces 725-0157. 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: damaged cutting blade, loose cutting blade, damaged flywheel key, engine needs tune up…

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

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

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

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…

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 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.…

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.…

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.…

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.

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.…

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.…

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.…