Troybilt
Gas Walk-Behind Mower

Model # 420 Official Troybilt lawn mower

Here are the diagrams and repair parts for Official Troybilt 420 lawn mower, 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 48 parts  |

Lawn Mower Blade Support (replaces 936-0524a) 736-0524B
#26

Rotary mower diagram

Lawn mower blade support (replaces 936-0524a)

Part #736-0524B

Replaced by #736-0524B-1

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Manufacturer substitution
This part replaces 736-0524B. Substitute parts can look different from the original.
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$6.58
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Yard Machines Lawn Tractor Flange Nut (replaces 00012173, Wd-129-103) 712-04065
#42

Rotary mower diagram

Yard machines lawn tractor flange nut (replaces 00012173, wd-129-103)

Part #712-04065

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This item is not returnable
$5.27
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Lawn Mower Control Cable 746-1130
#33

Rotary mower diagram

Lawn mower control cable

Part #746-1130

Replaced by #946-1130

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Manufacturer substitution
This part replaces 746-1130. Substitute parts can look different from the original.
This item is not returnable
$14.49
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Lawn Tractor Screw, 1/4-20 X 5/8-in (replaces 910-1652) 710-1652
#41

Rotary mower diagram

Lawn tractor screw, 1/4-20 x 5/8-in (replaces 910-1652)

Part #710-1652

This item is not returnable
$5.44
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Lawn & Garden Equipment Carriage Bolt (replaces 1186069, 583108, 706-101080, 706-10602-12, 791-182213) 710-0703
#12

Rotary mower diagram

Lawn & garden equipment carriage bolt (replaces 1186069, 583108, 706-101080, 706-10602-12, 791-182213)

Part #710-0703

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$6.46
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Yard Machines Lawn & Garden Equipment Wing Nut (replaces 01002925, 920-0279) 720-0279
#5

Rotary mower diagram

Yard machines lawn & garden equipment wing nut (replaces 01002925, 920-0279)

Part #720-0279

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$6.87
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Yard Machines Lawn & Garden Equipment Guide Bolt 710-1205
#6

Rotary mower diagram

Yard machines lawn & garden equipment guide bolt

Part #710-1205

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$5.01
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Blade Adapter 748-0377C
#22

Rotary mower diagram

Blade adapter

Part #748-0377C

Replaced by #748-0377E

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Manufacturer substitution
This part replaces 748-0377C. Substitute parts can look different from the original.
This item is not returnable
$26.00
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Lawn & Garden Equipment Hex Bolt (replaces 01000943, 910-1257) 710-1257
#24

Rotary mower diagram

Lawn & garden equipment hex bolt (replaces 01000943, 910-1257)

Part #710-1257

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$9.85
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Lawn Mower Lever 732-0404
#29

Rotary mower diagram

Lawn mower lever

Part #732-0404

Replaced by #94832

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Manufacturer substitution
This part replaces 732-0404. Substitute parts can look different from the original.
This item is not returnable
$17.05
10% OFF Phone Price : $19.05
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Symptoms for gas walk-behind mowers

Choose a symptom to see related walk-behind mower repairs.

Main causes: dirty carburetor, bad spark plug, clogged air filter, engine choke problems, clogged gas cap vent…

Main causes: stale gas, engine needs tune up, bad spark plug, dead battery, bad recoil starter, faulty safety switch, ba…

Main causes: uneven wheel height settings, damaged wheel, dull or damaged cutting blade…

Main causes: drive control cable failure, worn or broken drive belt, bad transmission, broken drive wheel…

Main causes: engine needs tune up, dirty or clogged carburetor, damaged flywheel key…

Main causes: damaged cutting blade, loose cutting blade, damaged flywheel key, engine needs tune up…

Repair guides for gas walk-behind mowers

These step-by-step repair guides will help you safely fix what’s broken on your walk-behind lawn mower.

How to replace a lawn mower recoil starter on an OHV engine

How to replace a lawn mower recoil starter on an OHV engine

Replace the recoil starter if it doesn't move when you pull the starter rope.…

Repair difficulty
Time required
 15 minutes or less
How to replace a lawn mower transmission

How to replace a lawn mower transmission

Learn how to replace the transmission on your lawn mower if it's locked up or won't drive the wheels.…

Repair difficulty
Time required
 60 minutes or less
How to replace a lawn mower carburetor

How to replace a lawn mower carburetor

The carburetor mixes air with fuel to drive the piston. Replace the carburetor if it's clogged or damaged.…

Repair difficulty
Time required
 15 minutes or less

Effective articles & videos to help repair your walk-behind mowers

Use the advice and tips in these articles and videos to get the most out of your walk-behind lawn mower.

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

Get answers to frequently asked questions about Sears and Sears PartsDirect.…

Types of walk-behind mower blades video

Types of walk-behind mower blades video

Learn about the different kinds of mower blades and how to maintain them.…