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  |

Lock Nut 3296-29
#22

Deck & wheel assembly (self propelled) diagram

Lock nut

Part #3296-29

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

Screw Engine 92-1624
#9

4 cycle engine, fuel tank & blade assembly diagram

Screw engine

Part #92-1624

Replaced by #95-1726

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Manufacturer substitution
This part replaces 92-1624. 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
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
Start Handle 612825
#3

Handle assembly 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
Tie Strap 614249
#13

Handle assembly diagram

Tie strap

Part #614249

Replaced by #614249

?
Manufacturer substitution
This part replaces 614249. Substitute parts can look different from the original.
This item is not returnable
In Stock
Spacer 62-6660
#11

Gear case assembly diagram

Spacer

Part #62-6660

Replaced by #62-6660

?
Manufacturer substitution
This part replaces 62-6660. Substitute parts can look different from the original.
This item is not returnable
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
Screw 32144-115
Screw

Part #32144-115

Replaced by #92-9665

?
Manufacturer substitution
This part replaces 32144-115. Substitute parts can look different from the original.
This item is not returnable
In Stock
Washer 40-1940
Washer

Part #40-1940

Replaced by #40-1940

?
Manufacturer substitution
This part replaces 40-1940. Substitute parts can look different from the original.
This item is not returnable
In Stock

Symptoms for gas walk-behind mowers

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

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

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

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

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

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…

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 rebuild a lawn mower carburetor

How to rebuild a lawn mower carburetor

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

Repair difficulty
Time required
 60 minutes or less
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 wheel

How to replace a lawn mower wheel

Learn how replace a damaged wheel on a walk-behind lawn mower—it's a quick, easy fix.…

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.…