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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Model diagram and schematic

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ALL PARTS
Showing 10 of 163 parts  |

Cap 699985

#957

All parts diagram

Cap

Part #699985

Replaced by #796577

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Manufacturer substitution
This part replaces 699985. Substitute parts can look different from the original.
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$20.69
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Lawn & Garden Equipment Engine Air Filter (replaces 392672, 393365, 49245, 690610, Bs-697029) 697029

#445

All parts diagram

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 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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Lawn & Garden Equipment Engine Recoil Starter (replaces Bs-497680) 497680

#608

All parts diagram

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

Part #497680

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Grip-str Rpe 281434

#60

All parts diagram

Grip-str rpe

Part #281434

Replaced by #281434S

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Manufacturer substitution
This part replaces 281434. Substitute parts can look different from the original.
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This item is not returnable
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Lawn & Garden Equipment Engine Carburetor Rebuild Kit (replaces 692703, 698155, 698157, 792385, Bs-692704, Bs-792385) 792383

#121

All parts diagram

Lawn & garden equipment engine carburetor rebuild kit (replaces 692703, 698155, 698157, 792385, bs-692704, bs-792385)

Part #792383

$35.39
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Carburetor 792385

#977

All parts diagram

Carburetor

Part #792385

Replaced by #792383

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Manufacturer substitution
This part replaces 792385. Substitute parts can look different from the original.
$35.39
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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 Float (replaces Bs-398187) 398187

#133

All parts diagram

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

Part #398187

This item is not returnable
$11.96
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In Stock

Symptoms for gas pressure washers

Choose a symptom to see related pressure washer repairs.

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

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

Main causes: broken recoil spring, damaged recoil starter…

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

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

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

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

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 check valve kit

How to install a pressure washer check valve kit

Air in the inlet water supply can damage the check valves. If the pump won’t build up pressure due to damaged check valv…

Repair difficulty
Time required
 120 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 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

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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What are the main components of a lawn mower?

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