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MTD
Front-Tine Tiller

Model # 21A-154A799 Official MTD front-tine tiller

Here are the diagrams and repair parts for Official MTD 21A-154A799 front-tine tiller, as well as links to manuals and error code tables, if available.

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Owner’s manual

Model diagram and schematic

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Yard Machines Lawn & Garden Equipment Lock Nut, 5/16-18 (replaces 753-05591) 712-04063
#6

Cultivator assembly diagram

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

Part #712-04063

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$4.40
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Yard Machines Lawn & Garden Equipment Nut 712-04064
#27

Cultivator assembly diagram

Yard machines lawn & garden equipment nut

Part #712-04064

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$4.49
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Bolt, Hex Wa 4543
#26

Cultivator assembly diagram

Bolt, hex wa

Part #4543

Replaced by #710-0599

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Manufacturer substitution
This part replaces 4543. Substitute parts can look different from the original.
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Knob-lower H 720-04052
#7

Cultivator assembly diagram

Knob-lower h

Part #720-04052

Replaced by #720-04072A

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Manufacturer substitution
This part replaces 720-04052. Substitute parts can look different from the original.
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Lawn Mower Wheel (replaces 734-04086) 734-1988
#50

Cultivator assembly diagram

Lawn mower wheel (replaces 734-04086)

Part #734-1988

This item is not returnable
$23.27
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Yard-man Lawn & Garden Equipment Carriage Bolt 710-0572
#3

Cultivator assembly diagram

Yard-man lawn & garden equipment carriage bolt

Part #710-0572

This item is not returnable
$6.57
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Outer Tine Assembly 686-0178
#23

Cultivator assembly diagram

Outer tine assembly

Part #686-0178

Replaced by #753-05987

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Manufacturer substitution
This part replaces 686-0178. Substitute parts can look different from the original.
$59.61
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Inner Tine Assembly 686-0177
#22

Cultivator assembly diagram

Inner tine assembly

Part #686-0177

Replaced by #753-05987

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Manufacturer substitution
This part replaces 686-0177. Substitute parts can look different from the original.
$59.61
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Lawn & Garden Equipment Hex Bolt 710-0597
#25

Cultivator assembly diagram

Lawn & garden equipment hex bolt

Part #710-0597

This item is not returnable
$5.80
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Ace Lawn & Garden Equipment Push Cap 726-0299
#49

Cultivator assembly diagram

Ace lawn & garden equipment push cap

Part #726-0299

This item is not returnable
$12.39
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14% OFF Phone Price : $14.39
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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...

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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...

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...

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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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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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