MTD
Rear-Tine Tiller

Model #21A-450 MTD rear tine gas tiller

Here are the diagrams and repair parts for MTD 21A-450 rear tine gas tiller, as well as links to manuals and error code tables, if available.


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Showing 10 of 161 parts

Lawn & Garden Equipment Flat Washer

#63

Handle/tine adapter/shield Diagram

Lawn & garden equipment flat washer

Part #736-0204
This item is not returnable
$2.91 | 
9% OFF MSRP:$3.20

In Stock

Lawn Tractor Screw

#13

Gear case assembly Diagram

Lawn tractor screw

Part #710-0604A
This item is not returnable
$2.99

In Stock

Lawn Tractor Screw

#11

Gear case assembly Diagram

Lawn tractor screw

Part #710-0376
This item is not returnable
$2.54 | 
23% OFF MSRP:$3.30

In Stock

Tiller Shift Rod Knob

#11

Handle/tine adapter/shield Diagram

Tiller shift rod knob

Part #720-0210A
$10.64 | 
11% OFF MSRP:$12.00

In Stock

Tiller Engine Pulley, Outer

#23

Outer and inner engine pulley/wheels Diagram

$10.16 | 
15% OFF MSRP:$12.00

In Stock

Tiller Gear Case Shaft Spur Gear

#23

Gear case assembly Diagram

$37.26 | 
9% OFF MSRP:$41.00

In Stock

Tiller Gear Case Shaft Spur Gear

#25

Gear case assembly Diagram

$55.90 | 
14% OFF MSRP:$65.00

In Stock

Lawn & Garden Equipment Flat Washer

#70

Handle/tine adapter/shield Diagram

Lawn & garden equipment flat washer

Part #736-3090
This item is not returnable
$5.13

In Stock

Tiller Engine Half Pulley, Inner

#22

Outer and inner engine pulley/wheels Diagram

$11.11

In Stock

Pin

#46

Handle/tine adapter/shield Diagram

Pin

Part #715-0120
This item is not returnable
$6.43 | 
21% OFF MSRP:$8.10

In Stock

Symptoms common to all tillers

Choose a symptom to see related tiller repairs.

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

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.

December 28, 2018

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

By Sears PartsDirect staff

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

November 1, 2016

A guide to garden tillers

By Sears PartsDirect staff

Rear tine tiller or front tine tiller, what to know to help in choosing the correct one for your needs.

November 1, 2015

Tiller common questions

By Sears PartsDirect staff

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