Onan
Lawn & Garden Engine

Model # B48G-GA020/3858C Official Onan gas engine

Here are the diagrams and repair parts for Official Onan B48G-GA020-3858C gas 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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Showing 10 of 297 parts  |

Line 503-0874
#38

Fuel system diagram

Line

Part #503-0874

Replaced by #30962

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Manufacturer substitution
This part replaces 503-0874. Substitute parts can look different from the original.
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This item is not returnable
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In Stock
Lock 5/16" - Code 21bj, 21bk, 21bw 850-0045
Lock 5/16" - code 21bj, 21bk, 21bw

Part #850-0045

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

Screw 800-0026
#22

Air housing diagram

Screw

Part #800-0026

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

Plug 167-0291
#9

Ignition diagram

Plug

Part #167-0291

Replaced by #909

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Manufacturer substitution
This part replaces 167-0291. Substitute parts can look different from the original.
This item is not returnable
In Stock
Flat Washer 526-0018
Flat washer

Part #526-0018

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

Washer 526-0113
#4

Starter motor parts diagram

Washer

Part #526-0113

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

Flat Washer 526-0122
#40

Cylinder block diagram

Flat washer

Part #526-0122

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

Deflector 145-0521
#10

Fuel system diagram

Deflector

Part #145-0521

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

Bearing 101-0450-10
#5C

Cylinder block diagram

Bearing

Part #101-0450-10

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

Cable 167-1595
#8A

Ignition diagram

Cable

Part #167-1595

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

Symptoms for gas ranges

Main causes: burner igniter switch failure, bad spark module, dirty or damaged spark electrode, wiring failure…

Main causes: gas supply problem, faulty pressure regulator, clogs in burner or orifice, control system failure, faulty t…

Repair guides for gas ranges

How to replace oven door hinges on a gas range

How to replace oven door hinges on a gas range

See how to replace the oven door hinges on a gas range yourself, in just 30 minutes.…

Repair difficulty
Time required
 15 minutes or less
How to replace a range spark module

How to replace a range spark module

Follow these step-by-step instructions to put the fire back into the surface burners on your gas range by replacing the …

Repair difficulty
Time required
 30 minutes or less
How to replace a range spark igniter switch

How to replace a range spark igniter switch

Follow these steps to replace the spark igniter switch—sometimes called a burner switch or spark switch—on a gas or dual…

Repair difficulty
Time required
 60 minutes or less

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