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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  |
Slotted Hex UP04155
#8

Shaft/spool/string/grass deflector diagram

Slotted hex

Part #UP04155

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

Head A98231A
#17

Shaft/spool/string/grass deflector diagram

Head

Part #A98231A

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

Nut UP04262
Nut

Part #UP04262

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

Square Head Screw UP04892
Square head screw

Part #UP04892

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

Cylinder Kit UP04136
#4

Engine internal diagram

Cylinder kit

Part #UP04136

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

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

Shaft UP04891
#4

Shaft/spool/string/grass deflector diagram

Shaft

Part #UP04891

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

Interlock UP03173
Interlock

Part #UP03173

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

Flange Washer UP03415
Flange washer

Part #UP03415

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.

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Why does my gas line trimmer run rough?

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

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Why won't my gas line trimmer start?

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

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Why does my gas line trimmer leak gas?

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

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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.

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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…

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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 …

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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…

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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.

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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.…

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Solving 3 common problems with line trimmer cutting lines

Solving 3 common problems with line trimmer cutting lines

Follow these tips to prevent the cutting line on your grass line trimmer from breaking or feeding out too much or too li…

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How to replace a line trimmer fuel line video

How to replace a line trimmer fuel line video

Follow the steps in this video to replace a leaking fuel line in a line trimmer.…

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