Makita
Gas Line Trimmer

Model # RBC321 Official Makita string trimmer

Here are the diagrams and repair parts for Official Makita RBC321 string trimmer, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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Showing 10 of 129 parts  |

Hex Wrench 783202-0
#404

String trimmer diagram

Hex wrench

Part #783202-0

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

Piston Ring (2) 598-25002-00
#61

String trimmer diagram

Piston ring (2)

Part #598-25002-00

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

Jet 503-60020-10
#111

String trimmer diagram

Jet

Part #503-60020-10

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

Plate 503-65003-00
#60

String trimmer diagram

Plate

Part #503-65003-00

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

Washer 523-60520-30
#122

String trimmer diagram

Washer

Part #523-60520-30

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

Spark Plug 065-01498-10
#92

String trimmer diagram

Spark plug

Part #065-01498-10

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

Line Trimmer Engine Oil 181115-A
#405

String trimmer diagram

Line trimmer engine oil

Part #181115-A

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

Starter Knob 521-50021-10
#67

String trimmer diagram

Starter knob

Part #521-50021-10

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

Washer M8 (2) 020-00899-10
#88

String trimmer diagram

Washer m8 (2)

Part #020-00899-10

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

Pipe Damper 1 627-15001-03
#96

String trimmer diagram

Pipe damper 1

Part #627-15001-03

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…