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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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13% OFF Phone Price : $7.57
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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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9% OFF Phone Price : $65.61
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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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9% OFF Phone Price : $65.61
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Lock Washer 1625
#32

Cultivator assembly diagram

Lock washer

Part #1625

This item is not returnable
$5.54
In Stock
Washer 736-0451
#12

Cultivator assembly diagram

Washer

Part #736-0451

This item is not returnable
$7.43
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...

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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...

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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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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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Tiller common questions

Tiller common questions

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

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