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 |

Lower boom & cutting head diagram

Hardware

Part #147539

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

#14

Handle and upper boom diagram

Spring

Part #610314

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

#31

Carburetor and muffler diagram

Module

Part #181067

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

#23

Cylinder and crankcase diagram

Plug

Part #181022

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

Lower boom & cutting head diagram

Coulping

Part #683605

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

#10

Clutch,starter module&fuel tank diagram

Pulley

Part #180535

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

#16

Cylinder head diagram

Valve

Part #181040

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

#22

Cylinder and crankcase diagram

O-ring

Part #181021

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

#15

Clutch,starter module&fuel tank diagram

Guide

Part #611061

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

Cylinder head diagram

Rocker arm

Part #181032

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

Model # 990R Official Ryobi string trimmer

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

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

Solving 3 common problems with line trimmer cutting lines

How to replace a line trimmer fuel line video

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