Model # 51974 (310000001 AND UP) Official Toro trimmer

Here are the diagrams and repair parts for Official Toro 51974-310000001-AND-UP 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 80 parts |

#41

Muffler/carburetor/fuel tank/housing diagram

Woodruff k

Part #690688001

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

#33

Muffler/carburetor/fuel tank/housing diagram

Washer

Part #690695001

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

Trimmer head/straight shaft/guard diagram

Adapter

Part #678019003

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

#17

Powerhead/upper shaft/handle diagram

Hex nut

Part #678029002

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

#26

Powerhead/upper shaft/handle diagram

Nut

Part #81068

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

#25

Powerhead/upper shaft/handle diagram

Clamp

Part #518020001

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

Trimmer head/straight shaft/guard diagram

Screw 1/

Part #660642001

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

#43

Muffler/carburetor/fuel tank/housing diagram

Screw, m4

Part #660349001

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

Powerhead/upper shaft/handle diagram

Line trimmer drive shaft, upper

Part #308159015

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

#26

Muffler/carburetor/fuel tank/housing diagram

Clip

Part #690699001

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 # 51974 (310000001 AND UP) Official Toro 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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