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MTD
Rear-Tine Tiller

Model # 21AA45M5031 Official MTD rear-tine tiller

Here are the diagrams and repair parts for Official MTD 21AA45M5031 rear-tine tiller, as well as links to manuals and error code tables, if available.

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Owner’s manual
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Showing 10 of 270 parts  |
Yard Machines Lawn & Garden Equipment Lock Nut, 5/16-18 (replaces 753-05591) 712-04063
#34

Handle & tine shield diagram

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
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Yard Machines Lawn & Garden Equipment Nut 712-04064
#41

Drive system 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
Yard Machines Lawn Tractor Flange Nut (replaces 00012173, Wd-129-103) 712-04065
#35

Handle & tine shield diagram

Yard machines lawn tractor flange nut (replaces 00012173, wd-129-103)

Part #712-04065

BEST SELLER
This item is not returnable
$5.27 | 
16% OFF Phone Price : $6.27
In Stock
Lawn Tractor Screw (replaces 01000628, 01000865, 1186307, 1186308, 791-180288, 791-683298, 910-0599) 710-0599
Lawn tractor screw (replaces 01000628, 01000865, 1186307, 1186308, 791-180288, 791-683298, 910-0599)

Part #710-0599

BEST SELLER
This item is not returnable
$4.91 | 
17% OFF Phone Price : $5.91
In Stock
Yard Machines Lawn & Garden Equipment Bell Washer (replaces 936-0242) 736-0242
Yard machines lawn & garden equipment bell washer (replaces 936-0242)

Part #736-0242

This item is not returnable
$6.58 | 
13% OFF Phone Price : $7.58
In Stock
Lawn & Garden Equipment Lock Washer 936-0119
#13

Drive system diagram

Lawn & garden equipment lock washer

Part #936-0119

This item is not returnable
$6.05 | 
14% OFF Phone Price : $7.05
In Stock
Ryobi Lawn Tractor Bolt (replaces 01000369, 1509-091, 1509-117, 153015, 706-10123-20, 706-501277-1, 710-0342, 910-3005) 710-3005
Ryobi lawn tractor bolt (replaces 01000369, 1509-091, 1509-117, 153015, 706-10123-20, 706-501277-1, 710-0342, 910-3005)

Part #710-3005

This item is not returnable
$5.11 | 
16% OFF Phone Price : $6.11
In Stock
Ryobi Lawn & Garden Equipment Flat Washer 736-0204
#38

Handle & tine shield diagram

Ryobi lawn & garden equipment flat washer

Part #736-0204

This item is not returnable
$5.43 | 
16% OFF Phone Price : $6.43
In Stock
Lawn Tractor Hex Bolt 710-3008
Lawn tractor hex bolt

Part #710-3008

This item is not returnable
$4.62 | 
18% OFF Phone Price : $5.62
In Stock
Lawn & Garden Equipment Hex Nut 912-3010
#10

Drive system diagram

Lawn & garden equipment hex nut

Part #912-3010

Replaced by #712-3010

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Manufacturer substitution
This part replaces 912-3010. Substitute parts can look different from the original.
$7.71
In Stock

Most common symptoms to help you fix your tillers

Choose a symptom to see related tiller repairs.

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Why do my tiller's tines turn but the wheels don't?

Main causes: clutch cable problems, faulty transmission…

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Why does my tiller turn the soil poorly?

Main causes: damaged tines, broken clevis pins, worn drive belt, faulty transmission, clutch cable problems, improper de…

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Why won't my tillers wheels or tines turn?

Main causes: worn or broken drive belts, bad transmission, clutch cable problems…

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Why does my tiller's engine leak oil or gas?

Main causes: leaky engine head gasket, damaged sump gasket, damaged oil drain plug seal, loose or cracked fuel line, lea…

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Why do my tiller's wheels turn but the tines don't?

Main causes: broken shaft clevis pins, transmission failure…

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Why does my tiller's engine run roughly or misfire?

Main causes: dirty carburetor, engine needs tune up, stale gas…

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Why won't my tiller's engine start?

Main causes: carburetor failure, bad gasoline, dirty spark plug, broken recoil starter…

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Most common repair guides to help fix your tillers

These step-by-step repair guides will help you safely fix what’s broken on your tiller.

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How to replace a tiller recoil starter

How to replace a tiller recoil starter

The recoil starter spins the engine when you pull the starter rope, and the rope retracts when released. If the recoil s…

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Repair difficulty
Time required
 15 minutes or less

Effective articles & videos to help repair your tillers

Use the advice and tips in these articles and videos to get the most out of your tiller.

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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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A guide to garden tillers

A guide to garden tillers

Rear tine tiller or front tine tiller, what to know to help in choosing the correct one for your needs.…

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Tiller common questions

Tiller common questions

These frequently asked questions might help you figure out what's wrong with your garden tiller.…

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