Lawn-Boy
Gas Walk-Behind Mower

Model # S21ZPR Official Lawn-Boy lawn mower

Here are the diagrams and repair parts for Official Lawn-Boy S21ZPR 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 185 parts  |

Screw 145498
#20

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
Belt, 21-in 683682
#32

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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In Stock
Wrist Pin 606608
#20

Engine group diagram

Wrist pin

Part #606608

Replaced by #94-5774

?
Manufacturer substitution
This part replaces 606608. Substitute parts can look different from the original.
In Stock
Start Handle 612825
#3

Starter group diagram

Start handle

Part #612825

Replaced by #81-1630

?
Manufacturer substitution
This part replaces 612825. Substitute parts can look different from the original.
In Stock
Bag Assembly 684168
Bag assembly

Part #684168

Replaced by #100-6362

?
Manufacturer substitution
This part replaces 684168. Substitute parts can look different from the original.
In Stock
Cap Screw 611393
#15

Engine group diagram

Cap screw

Part #611393

Replaced by #611393

?
Manufacturer substitution
This part replaces 611393. Substitute parts can look different from the original.
In Stock
Cable Screw 314576
#15

Carburetor group diagram

Cable screw

Part #314576

Replaced by #314576

?
Manufacturer substitution
This part replaces 314576. Substitute parts can look different from the original.
This item is not returnable
In Stock
Switch Kit 683968
#47

Engine group diagram

Switch kit

Part #683968

Replaced by #93-4307

?
Manufacturer substitution
This part replaces 683968. 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
Control Cable 683943
#18

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

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.…