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  |

Lock Washer 10040600
#28

Main frame diagram

Lock washer

Part #10040600

Replaced by #596238701

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Manufacturer substitution
This part replaces 10040600. Substitute parts can look different from the original.
BEST SELLER
This item is not returnable
$5.31
16% OFF Phone Price : $6.31
In Stock
Hitch Pin, 2-pack 4939M
#22

Main frame diagram

Hitch pin, 2-pack

Part #4939M

Replaced by #596919601

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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
Lock Nut 03510500
#16

Main frame diagram

Lock nut

Part #03510500

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

Head Assembly 794001
Head assembly

Part #794001

Replaced by #794327A

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Manufacturer substitution
This part replaces 794001. Substitute parts can look different from the original.
In Stock
Input Shaft 776040
#4

Right angle drive diagram

Input shaft

Part #776040

Replaced by #776040A

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Manufacturer substitution
This part replaces 776040. Substitute parts can look different from the original.
In Stock
Axle Bolt 4361H
#31

Main frame diagram

Axle bolt

Part #4361H

Replaced by #532179613

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Manufacturer substitution
This part replaces 4361H. Substitute parts can look different from the original.
This item is not returnable
In Stock
Output Shaft 776042
#5

Right angle drive diagram

Output shaft

Part #776042

Replaced by #776042

?
Manufacturer substitution
This part replaces 776042. Substitute parts can look different from the original.
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
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
Rh Cover 772034
#6

Right angle drive diagram

Rh cover

Part #772034

Replaced by #772034

?
Manufacturer substitution
This part replaces 772034. Substitute parts can look different from the original.
In Stock

Symptoms for gas walk-behind mowers

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

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

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

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

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

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...

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 rebuild a lawn mower carburetor

How to rebuild a lawn mower carburetor

The carburetor mixes air with fuel to drive the piston. Rebuild the carburetor if it's clogged or leaks....

Repair difficulty
Time required
60 minutes or less
How to replace a lawn mower recoil starter on an OHV engine

How to replace a lawn mower recoil starter on an OHV engine

Replace the recoil starter if it doesn't move when you pull the starter rope....

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

How to replace a lawn mower wheel

Learn how replace a damaged wheel on a walk-behind lawn mower—it's a quick, easy fix....

Repair difficulty
Time required
15 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.

How to enjoy all the online benefits we offer on our Sears PartsDirect website

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....

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....

Types of walk-behind mower blades video

Types of walk-behind mower blades video

Learn about the different kinds of mower blades and how to maintain them....