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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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

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

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 526-0122
#40

Cylinder block diagram

Flat washer

Part #526-0122

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

Lawn & Garden Equipment Engine Oil Pump Gasket Kit 120-0161
#2

Oil system diagram

Lawn & garden equipment engine oil pump gasket kit

Part #120-0161

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

Bearing 110-0197-10
#14D

Cylinder block diagram

Bearing

Part #110-0197-10

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

Elbow 502-0313
#32

Fuel system diagram

Elbow

Part #502-0313

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

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