Yard Machines
Front-Tine Tiller

Model #21A-24MK020 Official Yard Machines tiller

Here are the diagrams and repair parts for Yard Machines 21A-24MK020 tiller, as well as links to manuals and error code tables, if available.

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For DIY troubleshooting advice and repair guides, visit our repair help section.

Owner’s manual

Showing 10 of 73 parts

Lawn & Garden Equipment Lock Nut, 5/16-18 (replaces 753-05591)#39

Tiller Diagram

Lawn & garden equipment lock nut, 5/16-18 (replaces 753-05591)

Part #712-04063
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$3.26 | 
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MSRP: $4.90
Lawn & Garden Equipment Nut#30

Tiller Diagram

Lawn & garden equipment nut

Part #712-04064
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$3.05 | 
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MSRP: $5.00
Lawn Tractor Flange Nut (replaces 00012173, WD-129-103)#9

Tiller Diagram

Lawn tractor flange nut (replaces 00012173, wd-129-103)

Part #712-04065
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MSRP: $5.00
Lawn Tractor Gauge Wheel#51

Tiller Diagram

Lawn tractor gauge wheel

Part #734-0973
Replaced by #734-0973
?
Manufacturer substitution
This part replaces 734-0973. Substitute parts can look different from the original.
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$8.42 | 
11% OFF 
Phone Price: $9.42
Lawn Mower Handle Knob (replaces 01000382, 113589, 720-04072, 720-04125)#2

Tiller Diagram

Lawn mower handle knob (replaces 01000382, 113589, 720-04072, 720-04125)

Part #720-04072A
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MSRP: $8.50
Lawn & Garden Equipment Bell Washer (replaces 936-0242)#65

Tiller Diagram

Lawn & garden equipment bell washer (replaces 936-0242)

Part #736-0242
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Lawn Tractor Cotter Pin#22

Tiller Diagram

Lawn tractor cotter pin

Part #714-04043
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Tiller Clevis Pin (replaces 1817046, 711-0415)#19

Tiller Diagram

Tiller clevis pin (replaces 1817046, 711-0415)

Part #911-0415
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Tiller Tine Assembly (replaces 642-0003)#21

Tiller Diagram

Inner tine assembly

Part #642-0003
Replaced by #642-0003-0637
?
Manufacturer substitution
This part replaces 642-0003. Substitute parts can look different from the original.
BEST SELLER
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$81.99 | 
6% OFF 
Phone Price: $86.99
Tiller Tine Assembly (replaces 642-0004)#34

Tiller Diagram

Outer tine assembly

Part #642-0004
Replaced by #642-0004-0637
?
Manufacturer substitution
This part replaces 642-0004. Substitute parts can look different from the original.
In Stock
$81.17 | 
10% OFF 
Was: $90.19

Symptoms common to all tillers

Choose a symptom to see related tiller repairs.

Main causes: worn or broken drive belts, bad transmission, clutch cable problems
Main causes: broken shaft clevis pins, transmission failure
Main causes: dirty carburetor, engine needs tune up, stale gas
Main causes: carburetor failure, bad gasoline, dirty spark plug, broken recoil starter
Main causes: leaky engine head gasket, damaged sump gasket, damaged oil drain plug seal, loose or cracked fuel line, leaky carburetor seal
Main causes: damaged tines, broken clevis pins, worn drive belt, faulty transmission, clutch cable problems, improper depth-stake setting
Main causes: clutch cable problems, faulty transmission

Repair guides common to all tillers

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

May 1, 2013
By Lyle Weischwill
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 starter assembly is broken, follow the steps in this repair guide to replace it.

Repair difficulty
Time required
 15 minutes or less

Articles and videos common to all tillers

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

August 30, 2022

How to enjoy all the online benefits we offer on our Sears PartsDirect website

By Lyle Weischwill

Learn about all the convenient features on our Sears PartsDirect website that make your parts purchases easier.

December 28, 2018

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

By Kim Hillegass

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

November 1, 2015

Tiller common questions

By Lyle Weischwill

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