Model # TB4000 Official Troybilt trimmer

Here are the diagrams and repair parts for Official Troybilt TB4000 trimmer, as well as links to manuals and error code tables, if available.

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Owner’s manual

Model diagram and schematic

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ALL PARTS

Showing 10 of 155 parts |

Engine parts diagram

Push rod

Part #181033

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

#23

Engine parts diagram

Piston (3 piece oil ring_

Part #182300

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

#29

Engine parts diagram

Gear cam

Part #182124

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

#19

Boom and trimmer diagram

Housing

Part #181691

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

#37

Engine parts diagram

Screw

Part #181066

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

#35

Boom and trimmer diagram

Inner reel

Part #147495

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

Cylinder Head With Valve Seal (includes 10-14) 182306

#13

Engine parts diagram

Cylinder head with valve seal (includes 10-14)

Part #182306

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

#22

Boom and trimmer diagram

Gearbox

Part #182193

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

#NI07

All parts diagram

Reel and line assembly

Part #49U5001L063

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

#78

Engine parts diagram

Retaining ring

Part #181747

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 # TB4000 Official Troybilt 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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