Craftsman
Gas Walk-Behind Mower

Model # 91781320 Official Craftsman 32" rear discharge rotary cutting unit

Here are the diagrams and repair parts for Official Craftsman 91781320 32" rear discharge rotary cutting 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 58 parts  |

Hitch Pin, 2-pack 4939M
#22

Main frame diagram

Hitch pin, 2-pack

Part #4939M

Replaced by #596919601

?
Manufacturer substitution
This part replaces 4939M. Substitute parts can look different from the original.
This item is not returnable
$3.98
20% OFF Phone Price : $4.98
In Stock
Input Shaft 776040
#4

Right angle drive diagram

Input shaft

Part #776040

Replaced by #776040A

?
Manufacturer substitution
This part replaces 776040. Substitute parts can look different from the original.
In Stock
Head Assembly 794001
Head assembly

Part #794001

Replaced by #794327A

?
Manufacturer substitution
This part replaces 794001. Substitute parts can look different from the original.
In Stock
Screw 792027
#22

Right angle drive diagram

Screw

Part #792027

Replaced by #730636A

?
Manufacturer substitution
This part replaces 792027. Substitute parts can look different from the original.
In Stock
Gasket 788030
#13

Right angle drive diagram

Gasket

Part #788030

Replaced by #788030B

?
Manufacturer substitution
This part replaces 788030. Substitute parts can look different from the original.
This item is not returnable
In Stock
Cap Seal 786029
#15

Right angle drive diagram

Cap seal

Part #786029

Replaced by #786029

?
Manufacturer substitution
This part replaces 786029. Substitute parts can look different from the original.
$34.58
15% OFF Phone Price : $40.58
In Stock
Gear 778046
#3

Right angle drive diagram

Gear

Part #778046

Replaced by #778046

?
Manufacturer substitution
This part replaces 778046. Substitute parts can look different from the original.
In Stock
Lock Washer 10040600
#28

Main frame diagram

Lock washer

Part #10040600

Replaced by #596238701

?
Manufacturer substitution
This part replaces 10040600. Substitute parts can look different from the original.
This item is not returnable
$5.31
16% OFF Phone Price : $6.31
In Stock
Housing 770026
#2

Right angle drive diagram

Housing

Part #770026

Replaced by #770026A

?
Manufacturer substitution
This part replaces 770026. Substitute parts can look different from the original.
In Stock
Gasket 788028
#7

Right angle drive diagram

Gasket

Part #788028

Replaced by #788028

?
Manufacturer substitution
This part replaces 788028. Substitute parts can look different from the original.
This item is not returnable
In Stock

Symptoms for gas walk-behind mowers

Choose a symptom to see related walk-behind mower repairs.

Main causes: engine needs tune up, dirty or clogged carburetor, damaged flywheel key…

Main causes: uneven wheel height settings, damaged wheel, dull or damaged cutting blade…

Main causes: damaged cutting blade, loose cutting blade, damaged flywheel key, engine needs tune up…

Main causes: stale gas, engine needs tune up, bad spark plug, dead battery, bad recoil starter, faulty safety switch, ba…

Main causes: dirty carburetor, bad spark plug, clogged air filter, engine choke problems, clogged gas cap vent…

Main causes: drive control cable failure, worn or broken drive belt, bad transmission, broken drive wheel…

Repair guides for gas walk-behind mowers

These step-by-step repair guides will help you safely fix what’s broken on your walk-behind lawn mower.

How to replace a lawn mower spark plug

How to replace a lawn mower spark plug

Take a few minutes to replace the spark plug during your lawn mower's annual tune-up or if the spark plug is burnt or cr…

Repair difficulty
Time required
 15 minutes or less
How to replace a lawn mower blade

How to replace a lawn mower blade

Check your lawn mower blade regularly and replaced it if it's bent or damaged. …

Repair difficulty
Time required
 15 minutes or less
How to replace a lawn mower flywheel key on a flathead engine

How to replace a lawn mower flywheel key on a flathead engine

When you hit a hard object with your mower, the flywheel can shear to protect more expensive components. Learn how to re…

Repair difficulty
Time required
 45 minutes or less

Effective articles & videos to help repair your walk-behind mowers

Use the advice and tips in these articles and videos to get the most out of your walk-behind lawn mower.

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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.…

Introducing new technical repair content that we’re developing for the Sears Technical Institute

Introducing new technical repair content that we’re developing for the Sears Technical Institute

Learn about Sears Technical Institute and the advanced technical content being developed for aspiring appliance techs.…

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Top questions about Sears and Sears PartsDirect

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