Husqvarna
Rear-Engine Riding Mower

Model # ZTHQL4221A (968999172) Official Husqvarna riding lawn mower

Here are the diagrams and repair parts for Official Husqvarna ZTHQL4221A-968999172 riding lawn mower, 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 282 parts  |

Lawn & Garden Equipment Flat Washer 539990692
Lawn & garden equipment flat washer

Part #539990692

Replaced by #596134901

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Manufacturer substitution
This part replaces 539990692. Substitute parts can look different from the original.
BEST SELLER
This item is not returnable
$3.98
20% OFF Phone Price : $4.98
In Stock
Lawn Tractor Washer 539990122
#21

Park brake diagram

Lawn tractor washer

Part #539990122

Replaced by #596565301

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Manufacturer substitution
This part replaces 539990122. Substitute parts can look different from the original.
BEST SELLER
This item is not returnable
In Stock
Lawn Tractor Fuel Tank (replaces 5391044-09) 539104409
#2A

Main frame diagram

Lawn tractor fuel tank (replaces 5391044-09)

Part #539104409

BEST SELLER
$147.45
8% OFF Phone Price : $159.45
In Stock
Lawn Tractor Nut 539990585
#23

Motion control diagram

Lawn tractor nut

Part #539990585

Replaced by #596039201

?
Manufacturer substitution
This part replaces 539990585. Substitute parts can look different from the original.
This item is not returnable
In Stock
Lawn Tractor Lock Washer 539990247
Lawn tractor lock washer

Part #539990247

Replaced by #596238901

?
Manufacturer substitution
This part replaces 539990247. Substitute parts can look different from the original.
This item is not returnable
In Stock
Lawn Tractor Lock Washer 539990187
#7

Main frame diagram

Lawn tractor lock washer

Part #539990187

Replaced by #596238801

?
Manufacturer substitution
This part replaces 539990187. Substitute parts can look different from the original.
This item is not returnable
In Stock
Lawn Tractor Bolt 539990799
Lawn tractor bolt

Part #539990799

Replaced by #596039401

?
Manufacturer substitution
This part replaces 539990799. Substitute parts can look different from the original.
This item is not returnable
In Stock
Lawn Tractor Caster Wheel Spacer 539105543
#25

Main frame diagram

Lawn tractor caster wheel spacer

Part #539105543

This item is not returnable
$12.89
13% OFF Phone Price : $14.89
In Stock
Lawn Tractor Lug Nut 539101173
#1

Park brake diagram

Lawn tractor lug nut

Part #539101173

Replaced by #587653903

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Manufacturer substitution
This part replaces 539101173. Substitute parts can look different from the original.
This item is not returnable
$5.31
16% OFF Phone Price : $6.31
In Stock
Hcs, 5/16-18 X 2 3/4, Gr 539101721
#29

Deck lift diagram

Hcs, 5/16-18 x 2 3/4, gr

Part #539101721

This item is not returnable
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.

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

Main causes: faulty battery, bad alternator…

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

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

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

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

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

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

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

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.

How to replace a mandrel assembly on a riding lawn mower

How to replace a mandrel assembly on a riding lawn mower

Replace the mandrel assembly if the blade shaft vibrates or doesn't spin.…

Repair difficulty
Time required
 30 minutes or less
How to replace the flywheel key on a riding lawn mower

How to replace the flywheel key on a riding lawn mower

If the engine won't restart after hitting a stump or rock, the problem could be a sheared flywheel key. Follow these ste…

Repair difficulty
Time required
 60 minutes or less
How to replace a riding lawn mower ignition coil

How to replace a riding lawn mower ignition coil

If you're not getting spark from a good spark plug, the problem could be the ignition coil. Follow these step-by-step in…

Repair difficulty
Time required
 30 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.

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.…

How to remove a lawn mower blade using a removal tool

How to remove a lawn mower blade using a removal tool

Learn how a blade removal tool makes replacing the blade easier and safer…

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.…