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Craftsman
Front-Engine Lawn Tractor

Model # 9178400 Official Craftsman heavy-duty riding unit

Here are the diagrams and repair parts for Official Craftsman 9178400 heavy-duty riding unit, 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 208 parts  |
E-ring 98000071
E-ring

Part #98000071

Replaced by #812000029

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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
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
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
Washer 780001
#41

Transaxle diagram

Washer

Part #780001

Replaced by #780001

?
Manufacturer substitution
This part replaces 780001. Substitute parts can look different from the original.
This item is not returnable
$4.34
In Stock
Ball 792004
#10

Transaxle diagram

Ball

Part #792004

Replaced by #792004

?
Manufacturer substitution
This part replaces 792004. Substitute parts can look different from the original.
This item is not returnable
$4.37
In Stock
Ring 792018
#54

Transaxle diagram

Ring

Part #792018

Replaced by #792018

?
Manufacturer substitution
This part replaces 792018. Substitute parts can look different from the original.
This item is not returnable
$4.37
In Stock
Spring 792003
#9

Transaxle diagram

Spring

Part #792003

Replaced by #792003

?
Manufacturer substitution
This part replaces 792003. Substitute parts can look different from the original.
This item is not returnable
$4.37
In Stock
Gear 778036
#43

Transaxle diagram

Gear

Part #778036

Replaced by #778036

?
Manufacturer substitution
This part replaces 778036. Substitute parts can look different from the original.
$70.64
In Stock
Roll Pin 792002
#4

Transaxle diagram

Roll pin

Part #792002

Replaced by #792049

?
Manufacturer substitution
This part replaces 792002. Substitute parts can look different from the original.
This item is not returnable
$6.77
In Stock
Housing Assembly 782022
#46

Transaxle diagram

Housing assembly

Part #782022

Replaced by #782022A

?
Manufacturer substitution
This part replaces 782022. Substitute parts can look different from the original.
$140.40
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.

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

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

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Why does my riding mower run rough or misfire?

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

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Why won't my riding mower move?

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

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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…

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Why is my riding mower leaking oil or gas?

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

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Why does my riding mower creep in neutral?

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

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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

Why does my riding mower deck vibrate?

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

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

Main causes: faulty battery, bad alternator…

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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.

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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.…

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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.…

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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.…

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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.

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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.…

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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.…

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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.…

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