Lawn-Boy
Gas Walk-Behind Mower

Model # L21ZSNC Official Lawn-Boy walk-behind lawn mower

Here are the diagrams and repair parts for Official Lawn-Boy L21ZSNC walk-behind 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 244 parts  |

Nut 608311
Nut

Part #608311

The manufacturer no longer makes this part, and there's no substitute part

Belt, 21-in 683682
#22

Housing and shroud group diagram

Belt, 21-in

Part #683682

Replaced by #612543-03

?
Manufacturer substitution
This part replaces 683682. Substitute parts can look different from the original.

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$31.17
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In Stock
Idler Pulley 607978
#5

Drive group diagram

Idler pulley

Part #607978

Replaced by #607978

?
Manufacturer substitution
This part replaces 607978. Substitute parts can look different from the original.
In Stock
Bolster Hous 613876
#14

Housing and shroud group diagram

Bolster hous

Part #613876

Replaced by #613876

?
Manufacturer substitution
This part replaces 613876. Substitute parts can look different from the original.
In Stock
Hex Screw 613233
#34

Engine group diagram

Hex screw

Part #613233

Replaced by #613233

?
Manufacturer substitution
This part replaces 613233. Substitute parts can look different from the original.
This item is not returnable
In Stock
Washer 146304
#48

Drive group diagram

Washer

Part #146304

Replaced by #146304

?
Manufacturer substitution
This part replaces 146304. Substitute parts can look different from the original.
This item is not returnable
In Stock
Control Cable 683943
#11

Handle group diagram

Control cable

Part #683943

Replaced by #683943

?
Manufacturer substitution
This part replaces 683943. Substitute parts can look different from the original.
In Stock
Throttle Kit 684286

#NI

All parts diagram

Throttle kit

Part #684286

Replaced by #684286

?
Manufacturer substitution
This part replaces 684286. Substitute parts can look different from the original.
In Stock
Wire Lead Assembly 683821
#51

Engine group diagram

Wire lead assembly

Part #683821

Replaced by #683821

?
Manufacturer substitution
This part replaces 683821. Substitute parts can look different from the original.
In Stock
Pulley 609976
#2

Drive group diagram

Pulley

Part #609976

Replaced by #609976

?
Manufacturer substitution
This part replaces 609976. Substitute parts can look different from the original.
In Stock

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.…