Onan
Lawn & Garden Engine

Model # BF-MS/3394F Official Onan engine

Here are the diagrams and repair parts for Official Onan BF-MS-3394F 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 234 parts  |

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

Flat Washer 526-0214
#26

Governor, starter, alternator and air housing group diagram

Flat washer

Part #526-0214

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

Pre-clner 140-1259
#21

Fuel system group diagram

Pre-clner

Part #140-1259

Replaced by #45-083-01-S

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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
Washer 526-0113
Washer

Part #526-0113

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

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
17% OFF Phone Price : $30.09
In Stock
Flat Washer 526-0122
#7

Cylinder block group diagram

Flat washer

Part #526-0122

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

Flat Washer 526-0018
#5

Cylinder block group diagram

Flat washer

Part #526-0018

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

Clip 518-0004
#2

Governor, starter, alternator and air housing group diagram

Clip

Part #518-0004

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

Cable 167-1595
#18A

Breaker box and ignition group diagram

Cable

Part #167-1595

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

Washer 526-0066
Washer

Part #526-0066

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

Repair guides for front-engine lawn tractors

How to replace a blade clutch cable on a riding lawn mower

How to replace a blade clutch cable on a riding lawn mower

If the blades don't spin on your riding mower when you shift the lever, the blade clutch cable could be broken. Here’s h…

Repair difficulty
Time required
 30 minutes or less
How to replace the brake interlock switch on a riding lawn mower

How to replace the brake interlock switch on a riding lawn mower

If the engine won’t start even though the brake is on, the brake interlock switch could be at fault. Here’s how to repla…

Repair difficulty
Time required
 30 minutes or less
How to replace a riding lawn mower blade drive belt

How to replace a riding lawn mower blade drive belt

Replace the blade drive belt if it's broken or won't spin the cutting blades because of wear.…

Repair difficulty
Time required
 45 minutes or less

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