Onan
Lawn & Garden Engine

Model # B48M-GA018 Official Onan gas engine

Here are the diagrams and repair parts for Official Onan B48M-GA018 gas engine, as well as links to manuals and error code tables, if available.

There are a couple of ways to find the part or diagram you need:

  • Click a diagram to see the parts shown on that diagram.
  • In the search box below, enter all or part of the part number or the part’s name.

Not all parts are shown on the diagrams—those parts are labeled NI, for “not illustrated”.

We encourage you to save the model to your profile, so it’s easy to access parts and manuals for your appliance whenever you log in.

For DIY troubleshooting advice and repair guides, visit our repair help section.

Model diagram and schematic

SEARCH WITHIN THIS MODEL

?

This is the number corresponding to the part on the diagram / schematic

Search
ALL PARTS
Showing 10 of 263 parts  |

Filter 122-0338
#15

Oil system diagram

Filter

Part #122-0338

Replaced by #52-050-02-S1

?
Manufacturer substitution
This part replaces 122-0338. Substitute parts can look different from the original.
BEST SELLER
$14.24
12% OFF Phone Price : $16.24
In Stock
Plug 167-0298
#9

Ignition diagram

Plug

Part #167-0298

Replaced by #857

?
Manufacturer substitution
This part replaces 167-0298. Substitute parts can look different from the original.
This item is not returnable
In Stock
Flat Washer 526-0018
#39

Cylinder block diagram

Flat washer

Part #526-0018

Replaced by #STD551025

?
Manufacturer substitution
This part replaces 526-0018. Substitute parts can look different from the original.
This item is not returnable
$2.49
29% OFF Phone Price : $3.49
In Stock
Element 140-1216
#4

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
O-ring 509-0142
#25

Oil system diagram

O-ring

Part #509-0142

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

Cover 140-1168
#2

Fuel system diagram

Cover

Part #140-1168

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

Head 110-2563
#37B

Cylinder block diagram

Head

Part #110-2563

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

Roto Cap 110-0904
#38

Cylinder block diagram

Roto cap

Part #110-0904

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

Ring 113-0189-40
#4F

Piston and rod diagram

Ring

Part #113-0189-40

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

Effective articles & videos to help repair your lawn & garden engines

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.…