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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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  • 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”.

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For DIY troubleshooting advice and repair guides, visit our repair help section.

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

?
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
Lock Nut 03510500
Lock nut

Part #03510500

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
Gear 778033
#19

Transaxle diagram

Gear

Part #778033

Replaced by #778033A

?
Manufacturer substitution
This part replaces 778033. Substitute parts can look different from the original.
$119.52
In Stock
Diff Carrier 774028
#70

Transaxle diagram

Diff carrier

Part #774028

Replaced by #774028A

?
Manufacturer substitution
This part replaces 774028. Substitute parts can look different from the original.
$87.93
In Stock
Foot Pedal 4382H
#50

Main frame diagram

Foot pedal

Part #4382H

Replaced by #510089501

?
Manufacturer substitution
This part replaces 4382H. Substitute parts can look different from the original.
$8.54
In Stock
Housing Assembly 782023
#46A

Transaxle diagram

Housing assembly

Part #782023

Replaced by #782023A

?
Manufacturer substitution
This part replaces 782023. Substitute parts can look different from the original.
$129.40
In Stock
Screw 792007
#49

Transaxle diagram

Screw

Part #792007

Replaced by #792007

?
Manufacturer substitution
This part replaces 792007. Substitute parts can look different from the original.
This item is not returnable
$4.37
In Stock

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

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

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

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

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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 move?

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

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Time required
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 60 minutes or less

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