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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$7.89
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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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$19.94
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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 Spark Plug Wire Terminal (replaces 493880, 691234, Bs-493880s) 493880S

#851

All parts diagram

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

Part #493880S

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$4.75
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Lawn & Garden Equipment Engine Fuel Line Clamp 791850

#601

All parts diagram

Lawn & garden equipment engine fuel line clamp

Part #791850

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$4.74
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Lawn & Garden Equipment Engine Ignition Coil (replaces 695711, Bs-796964) 796964

#333

All parts diagram

Lawn & garden equipment engine ignition coil (replaces 695711, bs-796964)

Part #796964

$67.19
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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

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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.…