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 # 21AA412A000 Official MTD rear-tine tiller

Here are the diagrams and repair parts for Official MTD 21AA412A000 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 134 parts  |
Yard Machines Lawn & Garden Equipment Lock Nut, 5/16-18 (replaces 753-05591) 712-04063
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
#15

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
Back Order
Lock Washer 736-0119
#18

Drive system diagram

Lock washer

Part #736-0119

Replaced by #936-0119

?
Manufacturer substitution
This part replaces 736-0119. Substitute parts can look different from the original.
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
#28

Handle & tine shield diagram

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
Cap Screw 710-0258
#31

Gear case diagram

Cap screw

Part #710-0258

Replaced by #710-0751

?
Manufacturer substitution
This part replaces 710-0258. Substitute parts can look different from the original.
This item is not returnable
$5.12 | 
16% OFF Phone Price : $6.12
In Stock
Ryobi Lawn & Garden Equipment Flat Washer 736-0204
#16

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
Aircap Lawn & Garden Equipment Hex Screw 710-0896
Aircap lawn & garden equipment hex screw

Part #710-0896

This item is not returnable
$5.22 | 
16% OFF Phone Price : $6.22
In Stock
Ryobi Tiller Wheel Axle Oil Seal 721-0379
#4

Gear case diagram

Ryobi tiller wheel axle oil seal

Part #721-0379

This item is not returnable
$23.80 | 
20% OFF Phone Price : $29.80
In Stock
Lawn & Garden Equipment Screw 710-0606
#13

Drive system diagram

Lawn & garden equipment screw

Part #710-0606

This item is not returnable
$8.21 | 
11% OFF Phone Price : $9.21
In Stock

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
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.…

Read more

Parts & More