Briggs & Stratton
Lawn & Garden Engine

Model # 12S505-3856-B1 Official Briggs & Stratton engine

Here are the diagrams and repair parts for Official Briggs & Stratton 12S505-3856-B1 engine, as well as links to manuals and error code tables, if available.

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ALL PARTS
Showing 10 of 163 parts  |

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 Air Filter (replaces 392672, 393365, 49245, 690610, Bs-697029) 697029

#445

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Lawn & garden equipment engine air filter (replaces 392672, 393365, 49245, 690610, bs-697029)

Part #697029

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Lawn & Garden Equipment Engine Spark Plug 692051

#337

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Lawn & garden equipment engine spark plug

Part #692051

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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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Air Filter 273356

#967

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Air filter

Part #273356

Replaced by #273356S

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Manufacturer substitution
This part replaces 273356. Substitute parts can look different from the original.
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Lawn & Garden Equipment Engine Recoil Starter (replaces Bs-497680) 497680

#608

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Lawn & garden equipment engine recoil starter (replaces bs-497680)

Part #497680

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Grip-str Rpe 281434

#60

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Grip-str rpe

Part #281434

Replaced by #281434S

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This part replaces 281434. Substitute parts can look different from the original.
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Symptoms for gas pressure washers

Choose a symptom to see related pressure washer repairs.

Main causes: faulty unloader valve, bad pressure regulator…

Main causes: stale fuel, gummed up carburetor, engine needs tune up, throttle and choke controls need adjustment, bad re…

Main causes: dirty air filter, stale fuel, clogged or dirty carburetor, bad unloader valve…

Main causes: broken recoil spring, damaged recoil starter…

Main causes: overfilling engine with oil, improper fuel/air mixture, choke system problems, dirty carburetor, engine nee…

Main causes: pump running for more than 5 minutes when the spray wand isn't being used, faulty pressure relief valve, ba…

Main causes: insufficient water supply, clogged water inlet screen, clogged pressure hose, faulty pump check valves, stu…

Main causes: using a high-pressure spray tip when applying detergent, clogged siphon tube, chemical injection system fai…

Main causes: damaged recoil starter, oil inside cylinder, locked up engine piston…

Repair guides for gas pressure washers

These step-by-step repair guides will help you safely fix what’s broken on your pressure washer.

How to install a pressure washer chemical injection kit

How to install a pressure washer chemical injection kit

The chemical injection valve draws detergent into the pump. If it’s not drawing detergent, use a repair kit to replace t…

Repair difficulty
Time required
 15 minutes or less
How to install a pressure washer O-ring kit

How to install a pressure washer O-ring kit

O-rings seal fittings on the pressure washer pump. Damaged seals allow water to leak from the pump. Follow these steps t…

Repair difficulty
Time required
 45 minutes or less
How to replace a pressure washer pump

How to replace a pressure washer pump

The pump can be damaged by air in the inlet water supply or by chemicals that remain in the pump body after using the ch…

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 pressure washer.

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Top questions about Sears and Sears PartsDirect

Get answers to frequently asked questions about Sears and Sears PartsDirect.…

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What are the main components of a lawn mower?

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