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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
Lawn & Garden Equipment Engine Breaker Point Plunger 160-1151
#10

Ignition group diagram

Lawn & garden equipment engine breaker point plunger

Part #160-1151

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

Ring 113-0174
#16A

Crankshaft, flywheel, camshaft and piston group diagram

Ring

Part #113-0174

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

Fly Choke 142-0546
#19

Carburetor parts group diagram

Fly choke

Part #142-0546

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

Housing 140-1213
#12

Fuel system group diagram

Housing

Part #140-1213

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

(not Sold Separately) N/P
(not sold separately)

Part #N/P

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

Lawn & Garden Equipment Engine Screw 142-0016
#22

Carburetor parts group diagram

Lawn & garden equipment engine screw

Part #142-0016

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

Guide 110-1935
#38

Cylinder block group diagram

Guide

Part #110-1935

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

Washer 526-0065
#33

Gear cover, oil base and oil pump group diagram

Washer

Part #526-0065

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

Symptoms for gas walk-behind mowers

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Main causes: drive control cable failure, worn or broken drive belt, bad transmission, broken drive wheel…

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Why does my lawn mower run rough?

Main causes: engine needs tune up, dirty or clogged carburetor, damaged flywheel key…

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Why does my lawn mower stall?

Main causes: dirty carburetor, bad spark plug, clogged air filter, engine choke problems, clogged gas cap vent…

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Why does my lawn mower vibrate a lot?

Main causes: damaged cutting blade, loose cutting blade, damaged flywheel key, engine needs tune up…

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Main causes: stale gas, engine needs tune up, bad spark plug, dead battery, bad recoil starter, faulty safety switch, ba…

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Why does my lawn mower cut unevenly?

Main causes: uneven wheel height settings, damaged wheel, dull or damaged cutting blade…

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Repair guides for gas walk-behind mowers

These step-by-step repair guides will help you safely fix what’s broken on your walk-behind lawn mower.

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How to replace a lawn mower spark plug

How to replace a lawn mower spark plug

Take a few minutes to replace the spark plug during your lawn mower's annual tune-up or if the spark plug is burnt or cr…

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Repair difficulty
Time required
 15 minutes or less
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Repair difficulty
Time required
 60 minutes or less
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These step-by-step instructions show how to replace a broken starter pull rope on a walk-behind lawn mower.…

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Time required
 30 minutes or less

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

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