Can’t find your part?   Contact us:
+1-309-603-4777
Sears Parts Direct
Orders

  • Keep track of the models you own in your profile

    Sign in or Register to view or add models

Schedule a repair
MTD
Rear-Tine Tiller

Model # 21AA45M5099 Official MTD rear-tine tiller

Here are the diagrams and repair parts for Official MTD 21AA45M5099 rear-tine tiller, 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.

Owner’s manual

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 166 parts  |
Yard Machines Lawn & Garden Equipment Lock Nut, 5/16-18 (replaces 753-05591) 712-04063
#34

Handles/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
In Stock
Yard Machines Lawn & Garden Equipment Nut 712-04064
#41

Engine/tines/wheels 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

Handles/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
Tiller Drive Belt (replaces 754-0434) 954-0434
#22

Engine/tines/wheels diagram

Tiller drive belt (replaces 754-0434)

Part #954-0434

BEST SELLER

Get free shipping with Automatic Reorder

$45.41 | 
12% OFF Phone Price : $51.41
In Stock
Lawn Tractor Ball Bearing (replaces 01000340, 1185064, 741-0600, 941-0124, 95406) 941-0600
#45

Gears/housing diagram

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

Part #941-0600

BEST SELLER
$28.71 | 
17% OFF Phone Price : $34.71
In Stock
Tiller Wing Nut 712-0421
#36

Handles/tine shield diagram

Tiller wing nut

Part #712-0421

Replaced by #712-0421

?
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
#10

Engine/tines/wheels diagram

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

Part #742-0305A-0637

$19.50 | 
9% OFF Phone Price : $21.50
In Stock
Yard-man Lawn Tractor Cotter Pin 714-04043
#43

Engine/tines/wheels 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

Engine/tines/wheels diagram

Tiller clutch cable

Part #746-1117

Replaced by #946-1117

?
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

Handles/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

RECOMMENDED MAINTENANCE PARTS AND ACCESSORIES

Most common symptoms to help you fix your tillers

Choose a symptom to see related tiller repairs.

View all

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…

Read more

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

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

Read more

Why won't my tiller's engine start?

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

Read more

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.

View all
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…

Read more
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.

View all
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.…

Read more
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.…

Read more
Find the right carburetor assembly for a Craftsman snowblower, tiller or log splitter

Find the right carburetor assembly for a Craftsman snowblower, tiller or log splitter

This chart will help you find the right carburetor for your Craftsman snowblower, tiller or log splitter.…

Read more

Parts & More