Lauson
Lawn & Garden Engine

Model # LAV35-40919K Official Lauson 4-cycle engine

Here are the diagrams and repair parts for Official Lauson LAV35-40919K 4-cycle engine, 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 139 parts  |

Needl/seat 631021
#12

Carburetor no. 631612 diagram

Needl/seat

Part #631021

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

O-ring 631028
#25

Carburetor no. 631612 diagram

O-ring

Part #631028

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

Carburetor 631612
Carburetor

Part #631612

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

/carb Float 631023
#14

Carburetor no. 631612 diagram

/carb float

Part #631023

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

Fuel Fitting 631775
#26

Carburetor no. 631612 diagram

Fuel fitting

Part #631775

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

Element 31410
#54

Basic engine diagram

Element

Part #31410

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

Drain Plug 27244
#28

Basic engine diagram

Drain plug

Part #27244

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

Spring 31672
#9

Basic engine diagram

Spring

Part #31672

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

Governor Gear Assembly 30591
#33

Basic engine diagram

Governor gear assembly

Part #30591

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

Spool 30588A
#35

Basic engine diagram

Spool

Part #30588A

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

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 lawn & garden engines

Use the advice and tips in these articles and videos to get the most out of your walk-behind lawn mower.

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.…

What are the main components of a lawn mower?

What are the main components of a lawn mower?

Learn about the main parts of a lawn mower and when to replace parts.…