MTD
Gas Walk-Behind Mower

Model # 12AE997E099 Official MTD lawn mower

Here are the diagrams and repair parts for Official MTD 12AE997E099 lawn mower, as well as links to manuals and error code tables, if available.

There are a couple of ways to find the part or diagram you need:

  • Click a diagram to see the parts shown on that diagram.
  • In the search box below, enter all or part of the part number or the part’s name.

Not all parts are shown on the diagrams—those parts are labeled NI, for “not illustrated”.

We encourage you to save the model to your profile, so it’s easy to access parts and manuals for your appliance whenever you log in.

For DIY troubleshooting advice and repair guides, visit our repair help section.

Model diagram and schematic

SEARCH WITHIN THIS MODEL

?

This is the number corresponding to the part on the diagram / schematic

Search
ALL PARTS
Showing 10 of 281 parts  |

Blade-21" Mu 742-0741
#34

Handle/housing/grassbag diagram

Blade-21" mu

Part #742-0741

Replaced by #942-0741A

?
Manufacturer substitution
This part replaces 742-0741. Substitute parts can look different from the original.
BEST SELLER

Get free shipping with Automatic Reorder

$29.10
17% OFF Phone Price : $35.10
In Stock
Yard Machines Lawn & Garden Equipment Lock Nut, 5/16-18 (replaces 753-05591) 712-04063
Yard machines lawn & garden equipment lock nut, 5/16-18 (replaces 753-05591)

Part #712-04063

BEST SELLER
This item is not returnable
$4.40
19% OFF Phone Price : $5.40
In Stock
Yard Machines Lawn & Garden Equipment Nut 712-04064
#66

Handle/housing/grassbag diagram

Yard machines lawn & garden equipment nut

Part #712-04064

BEST SELLER
This item is not returnable
$4.49
18% OFF Phone Price : $5.49
In Stock
Knob 720-04072
#13

Handle/housing/grassbag diagram

Knob

Part #720-04072

Replaced by #720-04072A

?
Manufacturer substitution
This part replaces 720-04072. Substitute parts can look different from the original.
BEST SELLER
$9.33
10% OFF Phone Price : $10.33
In Stock
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

BEST SELLER
This item is not returnable
$5.44
16% OFF Phone Price : $6.44
In Stock
Wing Nut 712-0397
Wing nut

Part #712-0397

Replaced by #712-0397A

?
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
#14

Tranmission/wheels diagram

Lawn & garden equipment hex cap screw

Part #710-0751

This item is not returnable
$5.12
16% OFF Phone Price : $6.12
In Stock
Sears Lawn Mower Roller Wheel 756-0625
#60

Handle/housing/grassbag diagram

Sears lawn mower roller wheel

Part #756-0625

This item is not returnable
$12.00
14% OFF Phone Price : $14.00
In Stock
Cable Tie 726-0240
Cable tie

Part #726-0240

Replaced by #726-0178

?
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
#47

Tranmission/wheels diagram

Lawn & garden equipment cable tie

Part #725-0157

Replaced by #726-0178

?
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.…