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Onan
Lawn & Garden Engine

Model # BG-MS3270A Official Onan engine

Here are the diagrams and repair parts for Official Onan BG-MS3270A 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 267 parts  |
Pre-clner 140-1259
#20

Fuel system 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
Element 140-1216
#13

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
Lawn & Garden Equipment Engine Flywheel Ring Gear 104-0779
#4

Crankshaft, flywheel, camshaft and piston group diagram

Lawn & garden equipment engine flywheel ring gear

Part #104-0779

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

Lawn & Garden Equipment Engine Pump Body Gasket 142-0542
#13

Carburetor parts diagram

Lawn & garden equipment engine pump body gasket

Part #142-0542

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

Spring 142-0544
#16

Carburetor parts diagram

Spring

Part #142-0544

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

Lawn & Garden Equipment Screw 104-0170
#21

Crankshaft, flywheel, camshaft and piston group diagram

Lawn & garden equipment screw

Part #104-0170

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

Gasket Kit 168-0130

#NI

All parts diagram

Gasket kit

Part #168-0130

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

Shim 104-0776
#10

Cylinder block diagram

Shim

Part #104-0776

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

Cap Screw 801-0050
#17

Gear cover, oil base and oil pump group diagram

Cap screw

Part #801-0050

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

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