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 |

#404

String trimmer diagram

Hex wrench

Part #783202-0

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

#13

String trimmer diagram

S.h. bolt m5x33 (4)

Part #011-90598-60

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

#73

String trimmer diagram

Bolt m6x6

Part #001-66061-60

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

#114

String trimmer diagram

Primer pump

Part #524-60011-50

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

#128

String trimmer diagram

Washer

Part #003-11040-00

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

#24

String trimmer diagram

Inner snap ring

Part #003-14240-00

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

String trimmer diagram

Gear case unit (incl. fig. 2-10, 23-28)

Part #627-30010-04

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

#97

String trimmer diagram

Pipe damper 2

Part #627-15002-03

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

#15

String trimmer diagram

Control lever

Part #625-50180-00

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

#72

String trimmer diagram

Bolt assembly (2)

Part #001-16052-00

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 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 run rough?

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

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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Top 10 electric lawn and garden tools for 2023

Model # RBC321 Official Makita string trimmer

Model diagram and schematic

SEARCH WITHIN THIS MODEL

Symptoms for gas line trimmers

Why won't my gas line trimmer start?

Why does my gas line trimmer run rough?

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

Top 10 electric lawn and garden tools for 2023

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

Grass line trimmer maintenance checklist

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