Briggs & Stratton
Lawn & Garden Engine

Model # 121002-3423-H8 Official Briggs & Stratton engine

Here are the diagrams and repair parts for Official Briggs & Stratton 121002-3423-H8 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 151 parts  |

Lawn & Garden Equipment Engine Air Filter (replaces 17211-2l8-000, 1759330, 1904481, 491588, 491588ms, 494245, 6.491-338, 691710, Bs-491588s) 491588S

#445

All parts diagram

Lawn & garden equipment engine air filter (replaces 17211-2l8-000, 1759330, 1904481, 491588, 491588ms, 494245, 6.491-338, 691710, bs-491588s)

Part #491588S

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Lawn & Garden Equipment Engine Fuel Line (replaces 1734994sm, 327290ma, 691050, 7012638yp, 7032016yp, 7032956yp, 7041996yp, 7076272yp, 7077351yp, 791866, 798512, 809322, 809499) 791766

#187

All parts diagram

Lawn & garden equipment engine fuel line (replaces 1734994sm, 327290ma, 691050, 7012638yp, 7032016yp, 7032956yp, 7041996yp, 7076272yp, 7077351yp, 791866, 798512, 809322, 809499)

Part #791766

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Lawn & Garden Equipment Engine Spark Plug (replaces Bs-691043) 691043

#337

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Lawn & garden equipment engine spark plug (replaces bs-691043)

Part #691043

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Lawn & Garden Equipment Engine Recoil Starter Pawl Friction Plate (replaces 281503, Bs-692299) 692299

#456

All parts diagram

Lawn & garden equipment engine recoil starter pawl friction plate (replaces 281503, bs-692299)

Part #692299

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Lawn & Garden Equipment Engine Fuel Line 791867

#187A

All parts diagram

Lawn & garden equipment engine fuel line

Part #791867

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$26.89
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Lawn & Garden Equipment Engine Fuel Shut-off Valve (replaces 692586, 698181) 698180

#958

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Lawn & garden equipment engine fuel shut-off valve (replaces 692586, 698181)

Part #698180

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Lawn & Garden Equipment Engine Spark Plug Wire Terminal (replaces 493880, 691234, Bs-493880s) 493880S

#851

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Lawn & garden equipment engine spark plug wire terminal (replaces 493880, 691234, bs-493880s)

Part #493880S

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Lawn & Garden Equipment Engine Oil Fill Cap (replaces 281658, 49-667, 66768, 692261, Bs-281658s) 281658S

#21

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Lawn & garden equipment engine oil fill cap (replaces 281658, 49-667, 66768, 692261, bs-281658s)

Part #281658S

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Lawn & Garden Equipment Engine Intake Gasket 692555

#51

All parts diagram

Lawn & garden equipment engine intake gasket

Part #692555

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Lawn & Garden Equipment Engine Carburetor 591299

#125

All parts diagram

Lawn & garden equipment engine carburetor

Part #591299

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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 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.…