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  |

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
Screw 145498
#18

Handle group diagram

Screw

Part #145498

Replaced by #614697

?
Manufacturer substitution
This part replaces 145498. Substitute parts can look different from the original.
This item is not returnable
In Stock
Adj Asy Lh 684341
#58

Housing and shroud group diagram

Adj asy lh

Part #684341

Replaced by #684341

?
Manufacturer substitution
This part replaces 684341. Substitute parts can look different from the original.
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
Retainer 610165
#3

Carburetor group diagram

Retainer

Part #610165

Replaced by #610165

?
Manufacturer substitution
This part replaces 610165. Substitute parts can look different from the original.
In Stock
Spring 611214
#35

Engine group diagram

Spring

Part #611214

Replaced by #611214

?
Manufacturer substitution
This part replaces 611214. Substitute parts can look different from the original.
In Stock
Nut 130743
#3

Engine group diagram

Nut

Part #130743

Replaced by #130743

?
Manufacturer substitution
This part replaces 130743. Substitute parts can look different from the original.
This item is not returnable
In Stock
Retainer 611213
#48

Engine group diagram

Retainer

Part #611213

Replaced by #611213

?
Manufacturer substitution
This part replaces 611213. Substitute parts can look different from the original.
This item is not returnable
In Stock
Repair Kit 683777

#NI

All parts diagram

Repair kit

Part #683777

Replaced by #683777

?
Manufacturer substitution
This part replaces 683777. Substitute parts can look different from the original.
In Stock
Case Control 611777
#29

Handle group diagram

Case control

Part #611777

Replaced by #611777

?
Manufacturer substitution
This part replaces 611777. 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: engine needs tune up, dirty or clogged carburetor, damaged flywheel key…

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

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

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

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

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

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 spark plug

How to replace a lawn mower spark plug

Take a few minutes to replace the spark plug during your lawn mower's annual tune-up or if the spark plug is burnt or cr…

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

How to replace a lawn mower blade

Check your lawn mower blade regularly and replaced it if it's bent or damaged. …

Repair difficulty
Time required
 15 minutes or less
How to replace a lawn mower flywheel key on a flathead engine

How to replace a lawn mower flywheel key on a flathead engine

When you hit a hard object with your mower, the flywheel can shear to protect more expensive components. Learn how to re…

Repair difficulty
Time required
 45 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.…

Introducing new technical repair content that we’re developing for the Sears Technical Institute

Introducing new technical repair content that we’re developing for the Sears Technical Institute

Learn about Sears Technical Institute and the advanced technical content being developed for aspiring appliance techs.…

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.…