Okuma
Lawn & Garden Engine

Model # 5.5 OHV Official Okuma engine

Here are the diagrams and repair parts for Official Okuma 55-OHV 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 113 parts  |

Bolt P54598
#93

Engine assembly diagram

Bolt

Part #P54598

The manufacturer no longer makes this part, and there's no substitute part

Snap Ring P54032
#14

Engine assembly diagram

Snap ring

Part #P54032

The manufacturer no longer makes this part, and there's no substitute part

Cylinder Head P54052
#22

Engine assembly diagram

Cylinder head

Part #P54052

The manufacturer no longer makes this part, and there's no substitute part

Valve Spring P54154
#66

Engine assembly diagram

Valve spring

Part #P54154

The manufacturer no longer makes this part, and there's no substitute part

Exhaust Gasket P54590
#89

Engine assembly diagram

Exhaust gasket

Part #P54590

The manufacturer no longer makes this part, and there's no substitute part

Cylinder Head P54064
#27

Engine assembly diagram

Cylinder head

Part #P54064

The manufacturer no longer makes this part, and there's no substitute part

Oil Dipstick P54086
#37

Engine assembly diagram

Oil dipstick

Part #P54086

The manufacturer no longer makes this part, and there's no substitute part

Bolt P54058
#24

Engine assembly diagram

Bolt

Part #P54058

The manufacturer no longer makes this part, and there's no substitute part

Air Cleaner P54168
#73

Engine assembly diagram

Air cleaner

Part #P54168

The manufacturer no longer makes this part, and there's no substitute part

Crankcase P54012
#5

Engine assembly diagram

Crankcase

Part #P54012

The manufacturer no longer makes this part, and there's no substitute part

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

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.…