Briggs & Stratton
Lawn & Garden Engine

Model # 126M02-1378-B1 Official Briggs & Stratton engine

Here are the diagrams and repair parts for Official Briggs & Stratton 126M02-1378-B1 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 138 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 Carburetor Primer Bulb (replaces 496115, Bs-694395) 694395

#976

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Lawn & garden equipment engine carburetor primer bulb (replaces 496115, bs-694395)

Part #694395

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Lawn & Garden Equipment Engine Recoil Starter Rope (replaces 692259) 697316

#58

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Lawn & garden equipment engine recoil starter rope (replaces 692259)

Part #697316

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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

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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 Fuel Tank (replaces 693377, Bs-699374) 699374

#972

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Lawn & garden equipment engine fuel tank (replaces 693377, bs-699374)

Part #699374

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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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Spark Plug 799876

#337

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Spark plug

Part #799876

Replaced by #591868

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Manufacturer substitution
This part replaces 799876. Substitute parts can look different from the original.
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Lawn & Garden Equipment Engine Recoil Starter Handle (replaces 281434, 691930, 795426, Bs-281434s) 281434S

#60

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Lawn & garden equipment engine recoil starter handle (replaces 281434, 691930, 795426, bs-281434s)

Part #281434S

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Lawn & Garden Equipment Engine Carburetor Float (replaces Bs-398187) 398187

#133

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

Part #398187

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

#456

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

Part #692299

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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.…