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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

?
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
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

Bearing 780013
#57

Transaxle diagram

Bearing

Part #780013

Replaced by #780013

?
Manufacturer substitution
This part replaces 780013. Substitute parts can look different from the original.
$23.83
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.
$64.24
In Stock
Shiftr Rod 784055
#14

Transaxle diagram

Shiftr rod

Part #784055

Replaced by #784055

?
Manufacturer substitution
This part replaces 784055. Substitute parts can look different from the original.
$17.86
In Stock
Screw 17860412
#59

Seat and drive assembly diagram

Screw

Part #17860412

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

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.
$79.96
In Stock
Gear 778039
#53

Transaxle diagram

Gear

Part #778039

Replaced by #799023

?
Manufacturer substitution
This part replaces 778039. Substitute parts can look different from the original.
$119.68
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

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 charge a dead battery on my riding mower?

Main causes: faulty battery, bad alternator...

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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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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 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...

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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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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 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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Repair difficulty
Time required
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How to rebuild a riding lawn mower carburetor

Get your sputtering carburetor running smoothly in 60 minutes....

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