Snapper
Rear-Engine Riding Mower

Model # M300921B Official Snapper rear-engine riding lawn mower

Here are the diagrams and repair parts for Official Snapper M300921B rear-engine riding lawn mower, 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 462 parts  |

Filter 1-4359
#5

Fuel tank & operation seat diagram

Filter

Part #1-4359

Replaced by #394358S

?
Manufacturer substitution
This part replaces 1-4359. Substitute parts can look different from the original.
This item is not returnable
$6.91
13% OFF Phone Price : $7.91
In Stock
Clamp 1-2222
#6

Fuel tank & operation seat diagram

Clamp

Part #1-2222

Replaced by #791850

?
Manufacturer substitution
This part replaces 1-2222. Substitute parts can look different from the original.
This item is not returnable
$4.74
17% OFF Phone Price : $5.74
In Stock
Contro, Throttle (series 19) (23.6" Long) 2-2751
#1

Throttle control diagram

Contro, throttle (series 19) (23.6" long)

Part #2-2751

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

Cap, Hub (left Hand) 2-3522
#16

Wheels - rear diagram

Cap, hub (left hand)

Part #2-3522

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

Weldment, Spindle Housing 4-0460
#4

Spindle diagram

Weldment, spindle housing

Part #4-0460

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

Wheel Weight (8" Wheels) (all Rear Engine Riders) 6-0517

#NI03

All parts diagram

Wheel weight (8" wheels) (all rear engine riders)

Part #6-0517

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

Pulley Hub 1-5290
#19

Belts, brakes, interlock diagram

Pulley hub

Part #1-5290

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

Slide Bracket 4-7190
#27

Smooth clutch diagram

Slide bracket

Part #4-7190

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

Solenoid 1-8817
#2

Electrical system (electric start) diagram

Solenoid

Part #1-8817

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

Bolt, 5/16-18 X 1" Hex Flange Lock, Grad 5 (4) 9-1525
#20

Cutting decks, deflectors diagram

Bolt, 5/16-18 x 1" hex flange lock, grad 5 (4)

Part #9-1525

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

Most common symptoms to help you fix your riding mowers & tractors

Choose a symptom to see related riding mower and lawn tractor repairs.

Main causes: punctured tire or inner tube, leaky valve stem, damaged wheel rim…

Main causes: clogged carburetor, damaged flywheel key, dirty spark plug, stale fuel, improper valve lash, engine needs a…

Main causes: worn or broken ground drive belt, bad seat switch, transaxle freewheel control engaged, transaxle failure, …

Main causes: damaged tie rods, bent or worn wheel spindle, worn front axle, damaged sector gear assembly…

Main causes: engine overfilled with oil, leaky head gasket or sump gasket, damaged carburetor seals, cracked fuel pump, …

Main causes: shift lever needs adjustment, neutral control needs adjustment…

Main causes: worn or broken blade belt, broken belt idler pulley, blade clutch cable failure, bad PTO switch, damaged ma…

Main causes: damaged cutting blade, worn deck pulley, damaged mandrel pulley, loose fasteners on mower deck components…

Main causes: faulty battery, bad alternator…

Most common repair guides to help fix your riding mowers & tractors

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

How to replace a riding lawn mower rear tire

How to replace a riding lawn mower rear tire

Your mower can’t run on a damaged rear tire. Here’s how to install a new one.…

Repair difficulty
Time required
 60 minutes or less
How to replace a riding lawn mower blade

How to replace a riding lawn mower blade

If a blade on your mower is dull or bent, replace it following the steps in this repair guide.…

Repair difficulty
Time required
 30 minutes or less
How to replace a riding lawn mower fuel filter

How to replace a riding lawn mower fuel filter

Help your mower run better by replacing the fuel filter during your riding mower's annual tune-up.…

Repair difficulty
Time required
 15 minutes or less

Effective articles & videos to help repair your riding mowers & tractors

Use the advice and tips in these articles and videos to get the most out of your riding mower or lawn tractor.

How to remove a lawn mower blade using a removal tool

How to remove a lawn mower blade using a removal tool

Learn how a blade removal tool makes replacing the blade easier and safer…

Charging a battery in a riding lawn mower video

Charging a battery in a riding lawn mower video

Learn how to use a battery charger if your mower battery is dead.…

Riding mower and tractor common questions

Riding mower and tractor common questions

You might find the answers to your questions about your riding mower or lawn tractor in this list of frequently asked qu…