Briggs & Stratton
Lawn & Garden Engine

Model # 120202-3780-B1 Official Briggs & Stratton engine

Here are the diagrams and repair parts for Official Briggs & Stratton 120202-3780-B1 engine, as well as links to manuals and error code tables, if available.

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ALL PARTS
Showing 10 of 159 parts  |

Lawn & Garden Equipment Engine Recoil Starter Pulley (replaces 263074, 281504, Bs-498144) 498144
Lawn & garden equipment engine recoil starter pulley (replaces 263074, 281504, bs-498144)

Part #498144

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Snowblower Carburetor 791077

#125

All parts diagram

Snowblower carburetor

Part #791077

Replaced by #798653

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Manufacturer substitution
This part replaces 791077. Substitute parts can look different from the original.
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$57.71
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Lawn & Garden Equipment Engine Recoil Starter Pawl (replaces 281505, 692260, Bs-281505s) 281505S

#459

All parts diagram

Lawn & garden equipment engine recoil starter pawl (replaces 281505, 692260, bs-281505s)

Part #281505S

This item is not returnable
$5.80
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Lawn & Garden Equipment Engine Carburetor Rebuild Kit (replaces 696998, 792007, Bs-696998, Bs-792006) 792006

#121

All parts diagram

Lawn & garden equipment engine carburetor rebuild kit (replaces 696998, 792007, bs-696998, bs-792006)

Part #792006

$37.09
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Gasket 697001

#977

All parts diagram

Gasket

Part #697001

Replaced by #792006

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Manufacturer substitution
This part replaces 697001. Substitute parts can look different from the original.
$37.09
14% OFF Phone Price : $43.09
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Lawn & Garden Equipment Engine Carburetor Float (replaces Bs-398187) 398187

#133

All parts diagram

Lawn & garden equipment engine carburetor float (replaces bs-398187)

Part #398187

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$11.96
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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 Washer 271716

#276

All parts diagram

Lawn & garden equipment engine washer

Part #271716

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$6.19
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Lawn & Garden Equipment Engine Fuel Line 791867

#187A

All parts diagram

Lawn & garden equipment engine fuel line

Part #791867

This item is not returnable
$26.89
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Lawn & Garden Equipment Engine Fuel Shut-off Valve (replaces 692586, 698181) 698180

#958

All parts diagram

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

Part #698180

This item is not returnable
$19.94
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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.…