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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

BEST SELLER
This item is not returnable
$4.40 | 
19% OFF Phone Price : $5.40
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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

BEST SELLER
This item is not returnable
$4.49 | 
18% OFF Phone Price : $5.49
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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 | 
14% OFF Phone Price : $14.39
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Inner Tine Assembly 686-0179
#24

Cultivator assembly diagram

Inner tine assembly

Part #686-0179

Replaced by #753-05986

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Manufacturer substitution
This part replaces 686-0179. Substitute parts can look different from the original.
$54.19 | 
10% OFF Phone Price : $60.19
In Stock
Outer Tine Assembly 686-0176
#21

Cultivator assembly diagram

Outer tine assembly

Part #686-0176

Replaced by #753-05986

?
Manufacturer substitution
This part replaces 686-0176. Substitute parts can look different from the original.
$54.19 | 
10% OFF Phone Price : $60.19
In Stock
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
In Stock
Lawn Tractor Hex Bolt 710-0805
#4

Cultivator assembly diagram

Lawn tractor hex bolt

Part #710-0805

Replaced by #710-0805A

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Manufacturer substitution
This part replaces 710-0805. Substitute parts can look different from the original.
This item is not returnable
$7.43
In Stock
Lock Washer 1625
#32

Cultivator assembly diagram

Lock washer

Part #1625

This item is not returnable
$5.54
In Stock
Lawn & Garden Equipment Washer 4150
#19

Cultivator assembly diagram

Lawn & garden equipment washer

Part #4150

This item is not returnable
$5.20
In Stock
Upper Handle 731-05178
#9

Cultivator assembly diagram

Upper handle

Part #731-05178

This item is not returnable
$7.20
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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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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