Troybilt
Rear-Tine Tiller

Model # 21A-644H063 Official Troybilt tiller

Here are the diagrams and repair parts for Official Troybilt 21A-644H063 tiller, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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ALL PARTS
Showing 10 of 125 parts  |

Lawn Tractor Screw (replaces 01000628, 01000865, 1186307, 1186308, 791-180288, 791-683298, 910-0599) 710-0599
Lawn tractor screw (replaces 01000628, 01000865, 1186307, 1186308, 791-180288, 791-683298, 910-0599)

Part #710-0599

BEST SELLER
This item is not returnable
$4.91
17% OFF Phone Price : $5.91
In Stock
Lock Washer 736-0119
Lock washer

Part #736-0119

Replaced by #936-0119

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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
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
Lawn & Garden Equipment Cable Tie 725-0157
#13

Handle/cable assembly diagram

Lawn & garden equipment cable tie

Part #725-0157

Replaced by #726-0178

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Manufacturer substitution
This part replaces 725-0157. Substitute parts can look different from the original.
This item is not returnable
In Stock
Ace Lawn & Garden Equipment Flange Lock Nut 712-3004A
#7

Transmission assembly diagram

Ace lawn & garden equipment flange lock nut

Part #712-3004A

This item is not returnable
$4.92
17% OFF Phone Price : $5.92
In Stock
Lawn & Garden Equipment Hex Bolt 710-0459A
#32

Belt cover/guard/engine bracket diagram

Lawn & garden equipment hex bolt

Part #710-0459A

This item is not returnable
In Stock
Flat Washer GW-9929
#38

Belt cover/guard/engine bracket diagram

Flat washer

Part #GW-9929

This item is not returnable
In Stock
Ace Lawn & Garden Equipment Bolt 710-3103
#25

Belt cover/guard/engine bracket diagram

Ace lawn & garden equipment bolt

Part #710-3103

This item is not returnable
In Stock
Ryobi Lawn & Garden Equipment Flat Washer 736-3090
#30

Belt cover/guard/engine bracket diagram

Ryobi lawn & garden equipment flat washer

Part #736-3090

This item is not returnable
In Stock
Hex Nut 712-0121
#21

Handle/cable assembly diagram

Hex nut

Part #712-0121

This item is not returnable
In Stock

Most common symptoms to help you fix your tillers

Choose a symptom to see related tiller repairs.

Main causes: clutch cable problems, faulty transmission…

Main causes: damaged tines, broken clevis pins, worn drive belt, faulty transmission, clutch cable problems, improper de…

Main causes: worn or broken drive belts, bad transmission, clutch cable problems…

Main causes: leaky engine head gasket, damaged sump gasket, damaged oil drain plug seal, loose or cracked fuel line, lea…

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…

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.

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…

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.

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.…

Top questions about Sears and Sears PartsDirect

Top questions about Sears and Sears PartsDirect

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A guide to garden tillers

A guide to garden tillers

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