Onan
Lawn & Garden Engine

Model # BF-MS2666C Official Onan engine

Here are the diagrams and repair parts for Official Onan BF-MS2666C 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 236 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-cleaner 140-1218
#21

Fuel system group diagram

Pre-cleaner

Part #140-1218

Replaced by #45-083-01-S

?
Manufacturer substitution
This part replaces 140-1218. Substitute parts can look different from the original.
This item is not returnable
$7.29
12% OFF Phone Price : $8.29
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

Washer 526-0113
#27

Governor, starter, charging alt. & blower housing group diagram

Washer

Part #526-0113

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

Lock Nut 870-0277
#19

Crankshaft, flywheel, camshaft and piston group diagram

Lock nut

Part #870-0277

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

Flat Washer 526-0214
#26

Governor, starter, charging alt. & blower housing group diagram

Flat washer

Part #526-0214

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

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 806-0027
#42

Cylinder block group diagram

Screw

Part #806-0027

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

Gear 105-0353
#6

Crankshaft, flywheel, camshaft and piston group diagram

Gear

Part #105-0353

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

Repair guides for side-by-side refrigerators

How to replace a foamed-in-place door gasket in a side-by-side refrigerator

How to replace a foamed-in-place door gasket in a side-by-side refrigerator

The door gasket seals the gap around the door to keep the cold air in and the warm air out. Replace a worn or damaged do…

Repair difficulty
Time required
 30 minutes or less
How to replace a refrigerator water valve

How to replace a refrigerator water valve

Replace the water valve that feeds water to the ice maker and water dispenser if it no longer controls the flow of water…

Repair difficulty
Time required
 15 minutes or less
How to replace a defrost sensor in a side-by-side refrigerator

How to replace a defrost sensor in a side-by-side refrigerator

If frost is building up in the freezer of your side-by-side refrigerator, the defrost sensor could be at fault. You can …

Repair difficulty
Time required
 45 minutes or less

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.…