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Onan
Lawn & Garden Engine

Model # BF-MS3271E Official Onan engine

Here are the diagrams and repair parts for Official Onan BF-MS3271E 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 238 parts  |
Element 140-1216
#13

Fuel system group 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
Pre-clner 140-1259
#21

Fuel system group 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
Engine 18 B48M-3819A

#NI

All parts diagram

Engine 18

Part #B48M-3819A

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

Lock Flywheel Screw 821-0010
Lock flywheel screw

Part #821-0010

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

Screw 191-1048
#7

Starter group diagram

Screw

Part #191-1048

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

Valve 123-1175
#3

Cylinder block group diagram

Valve

Part #123-1175

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

Cap 505-0158
#22

Gear cover, oil base and oil pump group diagram

Cap

Part #505-0158

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

O-ring 142-0550
#24

Carburetor parts group diagram

O-ring

Part #142-0550

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

Lock Washer 850-0025
#19

Ignition group diagram

Lock washer

Part #850-0025

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

Float Lever 142-0548
#21

Carburetor parts group diagram

Float lever

Part #142-0548

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

Symptoms for gas cooktops

Why won't my cooktop's gas burners ignite or spark?

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

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Why do my cooktop's spark igniters keep clicking?

Main causes: stuck burner igniter switch, wet igniter switch contacts, faulty spark module…

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

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

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Repair guides for gas cooktops

How to replace a spark igniter switch on a gas cooktop

How to replace a spark igniter switch on a gas cooktop

Follow these step-by-step instructions to fix the surface burner ignition system on your gas cooktop by replacing the sp…

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Repair difficulty
Time required
 45 minutes or less
How to replace a spark module on a gas cooktop

How to replace a spark module on a gas cooktop

No flame on your gas cooktop? Installing a new spark module could be the fix you need.…

Read more
Repair difficulty
Time required
 30 minutes or less

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