Lawn-Boy
Gas Walk-Behind Mower

Model # 10210-3900001 AND UP Official Lawn-Boy lawn mower

Here are the diagrams and repair parts for Official Lawn-Boy 10210-3900001-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  |

Rope Guide 92-1021
#2

Handle assembly diagram

Rope guide

Part #92-1021

Replaced by #86-9671

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Manufacturer substitution
This part replaces 92-1021. Substitute parts can look different from the original.
This item is not returnable
$5.74
15% OFF Phone Price : $6.74
In Stock
Screw Engine 92-1624
#9

4 cycle engine, fuel tank & blade assembly diagram

Screw engine

Part #92-1624

Replaced by #95-1726

?
Manufacturer substitution
This part replaces 92-1624. 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
Knob 614243
#10

Handle assembly diagram

Knob

Part #614243

Replaced by #98-7134

?
Manufacturer substitution
This part replaces 614243. Substitute parts can look different from the original.
This item is not returnable
In Stock
Cage Nut - 1 613765
Cage nut - 1

Part #613765

Replaced by #613765

?
Manufacturer substitution
This part replaces 613765. Substitute parts can look different from the original.
This item is not returnable
In Stock
Collar Plate 677525
#11

4 cycle engine, fuel tank & blade assembly diagram

Collar plate

Part #677525

Replaced by #677525

?
Manufacturer substitution
This part replaces 677525. Substitute parts can look different from the original.
In Stock
Knob Ht Ajs 92-1008
Knob ht ajs

Part #92-1008

Replaced by #92-1008

?
Manufacturer substitution
This part replaces 92-1008. Substitute parts can look different from the original.
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
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
Shield Trai 92-1038
Shield trai

Part #92-1038

Replaced by #92-1038

?
Manufacturer substitution
This part replaces 92-1038. 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.…