MTD
Gas Walk-Behind Mower

Model # 12AE999P099 Official MTD lawn mower

Here are the diagrams and repair parts for Official MTD 12AE999P099 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 257 parts  |

Lawn Mower Blade Support (replaces 936-0524a) 736-0524B
#32

Handle/deck/chute diagram

Lawn mower blade support (replaces 936-0524a)

Part #736-0524B

Replaced by #736-0524B-1

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Manufacturer substitution
This part replaces 736-0524B. Substitute parts can look different from the original.
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$6.58
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Yard Machines Lawn & Garden Equipment Nut 712-04064
#66

Handle/deck/chute diagram

Yard machines lawn & garden equipment nut

Part #712-04064

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This item is not returnable
$4.49
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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

This item is not returnable
$5.44
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Lawn & Garden Equipment Hex Head Screw 710-0895
#38

Handle/deck/chute diagram

Lawn & garden equipment hex head screw

Part #710-0895

$8.20
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Lawn Mower Zone Control Cable (replaces 746-04639) 946-04639
#11

Handle/deck/chute diagram

Lawn mower zone control cable (replaces 746-04639)

Part #946-04639

This item is not returnable
$33.11
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Aircap Lawn Tractor Screw (replaces 150011, 910-0134) 710-0134
#61

Handle/deck/chute diagram

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

Part #710-0134

This item is not returnable
$6.55
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Lawn & Garden Equipment Push Cap (replaces 1917798, 926-0214) 726-0214
#53

Drive diagram

Lawn & garden equipment push cap (replaces 1917798, 926-0214)

Part #726-0214

This item is not returnable
$15.99
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Lawn Mower Wheel, Rear (replaces 734-2010a) 734-2010B
#6

Drive diagram

Lawn mower wheel, rear (replaces 734-2010a)

Part #734-2010B

$61.70
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Lawn Mower Blade Adapter (replaces 748-04225) 748-0377E
#31

Handle/deck/chute diagram

Lawn mower blade adapter (replaces 748-04225)

Part #748-0377E

This item is not returnable
$26.00
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Lawn Mower Zone Control Cable (replaces 746-0711a, 746-0711b) 946-0711B
#7

Handle/deck/chute diagram

Lawn mower zone control cable (replaces 746-0711a, 746-0711b)

Part #946-0711B

$32.85
15% OFF Phone Price : $38.85
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.

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.…

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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Top questions about Sears and Sears PartsDirect

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