Lawn-Boy
Gas Walk-Behind Mower

Model # 10302-3900001 AND UP Official Lawn-Boy lawn mower

Here are the diagrams and repair parts for Official Lawn-Boy 10302-3900001-AND-UP 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 122 parts  |

Pivot Stop 92-5412
#5

Handle assembly diagram

Pivot stop

Part #92-5412

Replaced by #107-0757

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Manufacturer substitution
This part replaces 92-5412. Substitute parts can look different from the original.
This item is not returnable
In Stock
Washer 614426
#19

Rear axle assembly diagram

Washer

Part #614426

Replaced by #614426

?
Manufacturer substitution
This part replaces 614426. Substitute parts can look different from the original.
This item is not returnable
In Stock
Screw 614697
#9

Handle assembly diagram

Screw

Part #614697

Replaced by #614697

?
Manufacturer substitution
This part replaces 614697. Substitute parts can look different from the original.
This item is not returnable
In Stock
Belt, 21-in 612543
#12

4 cycle engine, fuel tank & blade assembly diagram

Belt, 21-in

Part #612543

Replaced by #612543-03

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Manufacturer substitution
This part replaces 612543. Substitute parts can look different from the original.

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$31.17
19% OFF Was : $38.29
In Stock
Wheel Tire 684776
Wheel tire

Part #684776

Replaced by #684776

?
Manufacturer substitution
This part replaces 684776. Substitute parts can look different from the original.
This item is not returnable
$37.96
14% OFF Phone Price : $43.96
In Stock
Shoulder Bolt 92-1057
#17

Rear axle assembly diagram

Shoulder bolt

Part #92-1057

Replaced by #92-1057

?
Manufacturer substitution
This part replaces 92-1057. Substitute parts can look different from the original.
This item is not returnable
In Stock
Gear Case A 684766
#16

Deck & wheel assembly (self propelled) diagram

Gear case a

Part #684766

Replaced by #684766

?
Manufacturer substitution
This part replaces 684766. Substitute parts can look different from the original.
In Stock
Bushing Actuator 614673
#14

Deck & wheel assembly (self propelled) diagram

Bushing actuator

Part #614673

Replaced by #614673

?
Manufacturer substitution
This part replaces 614673. Substitute parts can look different from the original.
In Stock
Gear Cover 614668
#2

Gear case assembly diagram

Gear cover

Part #614668

Replaced by #614668-03

?
Manufacturer substitution
This part replaces 614668. Substitute parts can look different from the original.
In Stock
Upper Handle 614644
#1

Handle assembly diagram

Upper handle

Part #614644

Replaced by #614644

?
Manufacturer substitution
This part replaces 614644. 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

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