Onan
Lawn & Garden Engine

Model # B48G-GA018/3633A Official Onan engine

Here are the diagrams and repair parts for Official Onan B48G-GA018-3633A 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 247 parts  |

Pre-clner 140-1259
#20

Fuel system diagram

Pre-clner

Part #140-1259

Replaced by #45-083-01-S

?
Manufacturer substitution
This part replaces 140-1259. Substitute parts can look different from the original.
This item is not returnable
$7.29
12% OFF Phone Price : $8.29
In Stock
Flat Washer 526-0214
#3

Governor, starter charging alternator and blower housing diagram

Flat washer

Part #526-0214

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

Element 140-1216
#13

Fuel system diagram

Element

Part #140-1216

Replaced by #45-083-02-S

?
Manufacturer substitution
This part replaces 140-1216. Substitute parts can look different from the original.
This item is not returnable
$25.09
19% OFF Phone Price : $31.09
In Stock
Flat Washer 526-0018
#5

Cylinder block diagram

Flat washer

Part #526-0018

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

Screw 800-0545
#38A

Gear cover oil base and oil pump group diagram

Screw

Part #800-0545

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

Screw 815-0290
#24

Governor, starter charging alternator and blower housing diagram

Screw

Part #815-0290

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

Arm 150-1576
#10

Governor, starter charging alternator and blower housing diagram

Arm

Part #150-1576

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

Stud 150-1418
#21

Governor, starter charging alternator and blower housing diagram

Stud

Part #150-1418

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

Screw 800-0540
#39A

Cylinder block diagram

Screw

Part #800-0540

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

Brush 191-1041
#24

Starter parts diagram

Brush

Part #191-1041

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.…