MTD
Gas Walk-Behind Mower

Model #12A-948K299 MTD lawn mower

Here are the diagrams and repair parts for MTD 12A-948K299 lawn mower, as well as links to manuals and error code tables, if available.


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Showing 10 of 96 parts

Lawn Mower 21-in Deck Mulching Blade

#16

Handle/deck/chute Diagram

$18.55 | 
7% OFF MSRP:$20.00

In Stock

Lawn & Garden Equipment Lock Nut, 5/16-18

#3

Handle/deck/chute Diagram

Lawn & garden equipment lock nut, 5/16-18

Part #712-04063
This item is not returnable
$3.03 | 
24% OFF MSRP:$4.00

In Stock

Lawn Mower Blade Support

#18

Handle/deck/chute Diagram

Lawn mower blade support

Part #736-0524B
This item is not returnable
$4.93

In Stock

Lawn Mower Handle Knob

#30

Handle/deck/chute Diagram

Lawn mower handle knob

Part #720-04072A
This item is not returnable
$5.57 | 
26% OFF MSRP:$7.50

In Stock

Lawn & Garden Equipment Hex Head Screw

#22

Handle/deck/chute Diagram

Lawn & garden equipment hex head screw

Part #710-0895
This item is not returnable
$4.48

In Stock

Lawn & Garden Equipment Wing Nut

#42

Handle/deck/chute Diagram

Lawn & garden equipment wing nut

Part #712-0397A
This item is not returnable
$2.66 | 
17% OFF MSRP:$3.20

In Stock

Lawn & Garden Equipment Cotter Pin

#41

Handle/deck/chute Diagram

Lawn & garden equipment cotter pin

Part #914-0104
This item is not returnable
$2.85 | 
5% OFF MSRP:$3.00

In Stock

Lawn Mower Ground Drive Belt

#29

Handle/deck/chute Diagram

Lawn mower ground drive belt

Part #954-0460

Get free shipping with Automatic Reorder

$17.63

In Stock

Lawn Mower Hex Screw, 1/4-15 x 1-in

#14

Drive/wheels Diagram

Lawn mower hex screw, 1/4-15 x 1-in

Part #710-1241
This item is not returnable
$4.27 | 
16% OFF MSRP:$5.10

In Stock

Lawn & Garden Equipment Hex Cap Screw

#1

Drive/wheels Diagram

Lawn & garden equipment hex cap screw

Part #710-0751
This item is not returnable
$2.71 | 
13% OFF MSRP:$3.10

In Stock

Symptoms for gas walk-behind mowers

Choose a symptom to see related walk-behind mower repairs.

Main causes: drive control cable failure, worn or broken drive belt, bad transmission, broken drive wheel
Main causes: uneven wheel height settings, damaged wheel, dull or damaged cutting blade
Main causes: dirty carburetor, bad spark plug, clogged air filter, engine choke problems, clogged gas cap vent
Main causes: damaged cutting blade, loose cutting blade, damaged flywheel key, engine needs tune up
Main causes: engine needs tune up, dirty or clogged carburetor, damaged flywheel key
Main causes: stale gas, engine needs tune up, bad spark plug, dead battery, bad recoil starter, faulty safety switch, bad ignition coil

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 flywheel key on an OHV engine

The flywheel key couples the flywheel to the engine crankshaft. Replace the flywheel key if it's broken.

Repair difficulty
Time required
 60 minutes or less
April 1, 2013
By Lyle Weischwill
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
April 1, 2013
By Lyle Weischwill
How to replace a lawn mower safety switch

The safety switch stops the engine when you release the lever on the handle. This repair guide explains how to replace it if it's not working correctly.

Repair difficulty
Time required
 30 minutes or less

Articles and videos common to all walk-behind mowers

Use the advice and tips in these articles and videos to get the most out of your walk-behind lawn mower.

October 1, 2019

Types of walk-behind mower blades video

By Sears PartsDirect staff

Learn about the different kinds of mower blades and how to maintain them.