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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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Model diagram and schematic

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Showing 10 of 270 parts  |
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 | 
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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

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This item is not returnable
$5.27 | 
16% OFF Phone Price : $6.27
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Tiller Drive Belt (replaces 754-0434) 954-0434
#22

Drive system diagram

Tiller drive belt (replaces 754-0434)

Part #954-0434

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$45.41 | 
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Lawn Tractor Ball Bearing (replaces 01000340, 1185064, 741-0600, 941-0124, 95406) 941-0600
#45

Transmission assembly diagram

Lawn tractor ball bearing (replaces 01000340, 1185064, 741-0600, 941-0124, 95406)

Part #941-0600

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$28.71 | 
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Tiller Wing Nut 712-0421
#36

Handle & tine shield diagram

Tiller wing nut

Part #712-0421

Replaced by #712-0421

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Manufacturer substitution
This part replaces 712-0421. Substitute parts can look different from the original.
This item is not returnable
$2.49 | 
29% OFF Phone Price : $3.49
Back Order
Tiller Tine (replaces 742-0305-0637, 742-0305a) 742-0305A-0637
#51

Drive system diagram

Tiller tine (replaces 742-0305-0637, 742-0305a)

Part #742-0305A-0637

$20.09 | 
23% OFF Phone Price : $26.09
In Stock
Yard-man Lawn Tractor Cotter Pin 714-04043
#43

Drive system diagram

Yard-man lawn tractor cotter pin

Part #714-04043

This item is not returnable
$7.49 | 
12% OFF Phone Price : $8.49
In Stock
Tiller Clutch Cable 746-1117
#20

Drive system diagram

Tiller clutch cable

Part #746-1117

Replaced by #946-1117

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Manufacturer substitution
This part replaces 746-1117. Substitute parts can look different from the original.
$73.10 | 
8% OFF Phone Price : $79.10
In Stock
Lawn & Garden Equipment Hex Nut 912-0429
#10

Handle & tine shield diagram

Lawn & garden equipment hex nut

Part #912-0429

Replaced by #712-0429

?
Manufacturer substitution
This part replaces 912-0429. Substitute parts can look different from the original.
This item is not returnable
$7.06
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

?
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…

Read more

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…

Read more

Why won't my tillers wheels or tines turn?

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

Read more

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…

Read more

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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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.…

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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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