Model # UT20784 Official Homelite trimmer/brushcutter

Here are the diagrams and repair parts for Official Homelite UT20784 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 |

Engine internal diagram

Gasket

Part #UP03857

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

Shaft/spool/string/grass deflector diagram

Flex shaft

Part #UP04717

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

Screw

Part #UP03896

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

#10

Engine internal diagram

Cover

Part #UP00019

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

Engine internal diagram

Ring

Part #UP03838

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

Short block

Part #UP02994

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

Pulley

Part #UP03012

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

Interlock

Part #UP03173

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

Line trimmer blade

Part #UP04119

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

Washer

Part #UP04275

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…

Why won't my gas line trimmer start?

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

Why does my gas line trimmer leak gas?

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.

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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

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

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.

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Solving 3 common problems with line trimmer cutting lines

Model # UT20784 Official Homelite trimmer/brushcutter

Model diagram and schematic

SEARCH WITHIN THIS MODEL

Symptoms for gas line trimmers

Why does my gas line trimmer run rough?

Why won't my gas line trimmer start?

Why does my gas line trimmer leak gas?

Repair guides for gas line trimmers

How to rebuild a line trimmer carburetor

How to replace a line trimmer carburetor

How to replace a line trimmer fuel line

Articles and videos for gas line trimmers

Solving 3 common problems with line trimmer cutting lines

How to replace a line trimmer fuel line video

How to tune up a grass line trimmer video

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