Homelite
Gas Line Trimmer

Model # UT20780 Official Homelite trimmer/brushcutter

Here are the diagrams and repair parts for Official Homelite UT20780 trimmer/brushcutter, 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 141 parts  |

Clamp UP04105
#4

Shaft/spool/string/grass deflector diagram

Clamp

Part #UP04105

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

Lead UP04537
Lead

Part #UP04537

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

Cartridge Line D09365
#18

Shaft/spool/string/grass deflector diagram

Cartridge line

Part #D09365

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

Filter Assembly UP05084
#DA

Muffler/air cleaner diagram

Filter assembly

Part #UP05084

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

Screw UP04131
#2

Carburetor/fuel tank diagram

Screw

Part #UP04131

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

Screw UP03897
#14

Engine internal diagram

Screw

Part #UP03897

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

Washer UP04129
#28

Shaft/spool/string/grass deflector diagram

Washer

Part #UP04129

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

Start Grip UP03026
Start grip

Part #UP03026

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

Ring UP03838
#3

Engine internal diagram

Ring

Part #UP03838

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

Bumper UP03501
#13

Carburetor/fuel tank diagram

Bumper

Part #UP03501

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

Symptoms for gas line trimmers

Choose a symptom to see related grass line trimmer repairs.

Main causes: stale fuel, cracked fuel lines, dirty carburetor, bad spark plug, worn piston rings…

Main causes: stale fuel, clogged fuel filter, faulty spark plug, clogged air filter, cracked fuel lines, clogged carbure…

Main causes: cracked fuel lines, bad carburetor seals, leaky fuel tank cap, damaged fuel tank…

Repair guides for gas line trimmers

These step-by-step repair guides will help you safely fix what’s broken on your grass line trimmer.

How to rebuild a line trimmer carburetor

How to rebuild a line trimmer carburetor

If the line trimmer engine won't start even though there's fuel in the tank, the carburetor could be the problem. Follow…

Repair difficulty
Time required
 15 minutes or less
How to replace a line trimmer carburetor

How to replace a line trimmer carburetor

If the line trimmer won't start even though there's fuel in the tank, the carburetor could be the problem. Follow these …

Repair difficulty
Time required
 15 minutes or less
How to replace a line trimmer fuel line

How to replace a line trimmer fuel line

The fuel line on a grass line trimmer deteriorates with time and eventually can split or crack. You can replace it yours…

Repair difficulty
Time required
 15 minutes or less

Articles and videos for gas line trimmers

Use the advice and tips in these articles and videos to get the most out of your grass line trimmer.

Top 10 electric lawn and garden tools for 2023

Top 10 electric lawn and garden tools for 2023

Learn about the top 10 must-have electric lawn & garden tools for 2023…

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.…

Grass line trimmer maintenance checklist

Grass line trimmer maintenance checklist

Find out how to take care of your grass line trimmer from the start of the trimming season until the end, with this help…