Model # 990R Official Ryobi string trimmer

Here are the diagrams and repair parts for Official Ryobi 990R 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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ALL PARTS

Showing 10 of 155 parts |

Handle and upper boom diagram

Cable

Part #181093

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

#19

Cylinder and crankcase diagram

Gasket

Part #181018

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

#20

Lower boom & cutting head diagram

Spool

Part #147494

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

Lower boom & cutting head diagram

Screw

Part #683606

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

Handle and upper boom diagram

Cover

Part #181088

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

#13

Carburetor and muffler diagram

Screw

Part #181053

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

#NI

All parts diagram

Gasket kit

Part #181069

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

Lower boom & cutting head diagram

Hardware

Part #147539

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

#21

Clutch,starter module&fuel tank diagram

Pad

Part #181084

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

#30

Carburetor and muffler diagram

Ground tab

Part #611063

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 # 990R Official Ryobi 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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