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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

?
Manufacturer substitution
This part replaces 503-0874. Substitute parts can look different from the original.
This item is not returnable
$6.76 | 
13% OFF Phone Price : $7.76
In Stock
Plug 167-0291
#9

Ignition diagram

Plug

Part #167-0291

Replaced by #909

?
Manufacturer substitution
This part replaces 167-0291. Substitute parts can look different from the original.
This item is not returnable
$5.40
In Stock
Bypass Spring 120-0140
#8

Oil system diagram

Bypass spring

Part #120-0140

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

Cap Screw 800-0027
#26

Fuel system diagram

Cap screw

Part #800-0027

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

Screw 815-0470
#8

Fuel system diagram

Screw

Part #815-0470

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

Plug 517-0120
#18

Cylinder block diagram

Plug

Part #517-0120

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

Ring 113-0189-30
#4E

Piston and rod diagram

Ring

Part #113-0189-30

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

Lock Washer 850-0040
Lock washer

Part #850-0040

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

Bearing, Governor Shaft 510-0105
#2

Gearcase diagram

Bearing, governor shaft

Part #510-0105

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

Stator 191-1256
#1

Flywheel alternator - 15 ampere diagram

Stator

Part #191-1256

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

Symptoms for gas ranges

Why won't my range's gas burner spark or ignite?

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

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Why isn't my range's gas burner heating properly?

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

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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.…

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Repair difficulty
Time required
 15 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…

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Repair difficulty
Time required
 60 minutes or less
How to replace a range spark igniter electrode

How to replace a range spark igniter electrode

Learn how to replace the spark igniter electrode for the surface burners on a gas range or dual-fuel range.…

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Repair difficulty
Time required
 45 minutes or less

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