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Craftsman
Front-Engine Lawn Tractor

Model # 9178420 Official Craftsman heavy-duty riding unit

Here are the diagrams and repair parts for Official Craftsman 9178420 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 168 parts  |
Lever Housing 784061
Lever housing

Part #784061

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

Screw 21150406
#28

Generator diagram

Screw

Part #21150406

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

Screw 17850412
Screw

Part #17850412

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

Screw 17850514
Screw

Part #17850514

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

Gen Strap 5152H
#18

Generator diagram

Gen strap

Part #5152H

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

Idler Bracket 626A27
#49

Steering assembly diagram

Idler bracket

Part #626A27

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

Allen Screw 04250506
#87

Steering assembly diagram

Allen screw

Part #04250506

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

E-ring 98000073
#17

Steering assembly diagram

E-ring

Part #98000073

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

Screw 17910612
#63

Main frame diagram

Screw

Part #17910612

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

Spacer 4326H
#15

Main frame diagram

Spacer

Part #4326H

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.

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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…

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Why won't my riding mower start?

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

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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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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 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 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 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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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 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.…

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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.…

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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.…

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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.

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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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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…

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