Can’t find your part?   Contact us:
+1-309-603-4777
Sears Parts Direct
Orders

  • Keep track of the models you own in your profile

    Sign in or Register to view or add models

Schedule a repair
Craftsman
Front-Engine Lawn Tractor

Model # 9178321 Official Craftsman riding lawn mower

Here are the diagrams and repair parts for Official Craftsman 9178321 riding lawn mower, 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 219 parts  |
E-ring 98000071
E-ring

Part #98000071

Replaced by #812000029

?
Manufacturer substitution
This part replaces 98000071. Substitute parts can look different from the original.
BEST SELLER
This item is not returnable
$3.50
| 
22% OFF Phone Price : $4.50
In Stock
Lock Washer 10040600
#62

Wheel assembly diagram

Lock washer

Part #10040600

Replaced by #596238701

?
Manufacturer substitution
This part replaces 10040600. Substitute parts can look different from the original.
BEST SELLER
This item is not returnable
$5.31
| 
16% OFF Phone Price : $6.31
In Stock
Pin 786026
#50

Transaxle diagram

Pin

Part #786026

Replaced by #786026B

?
Manufacturer substitution
This part replaces 786026. Substitute parts can look different from the original.
BEST SELLER
This item is not returnable
$4.60
| 
18% OFF Phone Price : $5.60
In Stock
Lock Washer 10040500
#53

Wheel assembly diagram

Lock washer

Part #10040500

Replaced by #596238801

?
Manufacturer substitution
This part replaces 10040500. Substitute parts can look different from the original.
This item is not returnable
$5.11
In Stock
Washer 19252016
Washer

Part #19252016

Replaced by #532121749

?
Manufacturer substitution
This part replaces 19252016. Substitute parts can look different from the original.
This item is not returnable
$3.98
| 
20% OFF Phone Price : $4.98
In Stock
Nut 03520500
Nut

Part #03520500

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

Ring 792001
#3

Transaxle diagram

Ring

Part #792001

Replaced by #792001

?
Manufacturer substitution
This part replaces 792001. Substitute parts can look different from the original.
This item is not returnable
$4.37
In Stock
Lock Nut 03510500
Lock nut

Part #03510500

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

Screw 792020
#17

Transaxle diagram

Screw

Part #792020

Replaced by #792020

?
Manufacturer substitution
This part replaces 792020. Substitute parts can look different from the original.
This item is not returnable
$4.37
In Stock
Axle Rh 774045
#15B

Transaxle diagram

Axle rh

Part #774045

Replaced by #774068

?
Manufacturer substitution
This part replaces 774045. Substitute parts can look different from the original.
$95.40
In Stock

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

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

View all

Why is my riding mower not cutting evenly?

Main causes: unlevel mower deck, dull or damaged cutting blades, worn mandrel pulleys, bent mower deck, engine needs tun...

Read more

Why won't my riding mower start?

Main causes: dead battery, stale fuel, bad starter solenoid, ignition system problem, bad ignition interlock switch, clo...

Read more

Why is the steering loose on my riding mower?

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

Read more

How do I fix a flat tire on my riding mower?

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

Read more

Why won't my riding mower cut grass?

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

Read more

How do I charge a dead battery on my riding mower?

Main causes: faulty battery, bad alternator...

Read more

Why does my riding mower deck vibrate?

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

Read more

Why does my riding mower creep in neutral?

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

Read more

Why won't my riding mower move?

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

Read more

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.

View all
How to replace the seat switch on a riding lawn mower

How to replace the seat switch on a riding lawn mower

Follow the steps in this guide to install a new riding mower seat switch in about 15 minutes....

Read more
Repair difficulty
Time required
15 minutes or less
How to replace a riding lawn mower spark plug

How to replace a riding lawn mower spark plug

If the engine is hard to start or if the spark plug electrode is burnt or cracked, take 15 minutes to replace it....

Read more
Repair difficulty
Time required
15 minutes or less
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....

Read more
Repair difficulty
Time required
60 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.

View all
How to enjoy all the online benefits we offer on our Sears PartsDirect website

How to enjoy all the online benefits we offer on our Sears PartsDirect website

Learn about all the convenient features on our Sears PartsDirect website that make your parts purchases easier....

Read more
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....

Read more
Riding lawn mower engine clicks but doesn't turn over video

Riding lawn mower engine clicks but doesn't turn over video

Check the starter solenoid, starter motor, wiring, battery and engine....

Read more

Parts & More