Troybilt
Gas Line Trimmer

Model #TB425CS Troybilt 4-cycle gas trimmer

Here are the diagrams and repair parts for Troybilt TB425CS 4-cycle gas trimmer, as well as links to manuals and error code tables, if available.


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Not all parts are shown on the diagrams—those parts are labeled NI, for “not illustrated”.

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Showing 10 of 135 parts

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Line Trimmer Throttle Cable

#5

Boom and trimmer Diagram

$10.85

In Stock

J-handle

#6

Boom and trimmer Diagram

J-handle

Part #791-180687
?
Manufacturer substitution
This part replaces 791-180687. Substitute parts can look different from the original.
This part replaces 791-180687
$28.60

In Stock

Line Trimmer Screw

#52

Engine parts Diagram

Line trimmer screw

Part #9054
?
Manufacturer substitution
This part replaces 791-181020. Substitute parts can look different from the original.
This part replaces 791-181020
This item is not returnable
$2.70 | 
10% OFF MSRP:$3.00

In Stock

Lawn & Garden Equipment Engine Spark Plug

#NI01

All parts Diagram

Lawn & garden equipment engine spark plug

Part #RDZ19H
?
Manufacturer substitution
This part replaces 791-180852B. Substitute parts can look different from the original.
This part replaces 791-180852B
$10.83

In Stock

Line Trimmer Spool Seal

#41

Boom and trimmer Diagram

Line trimmer spool seal

Part #791-181467
?
Manufacturer substitution
This part replaces 791-181467. Substitute parts can look different from the original.
This part replaces 791-181467
This item is not returnable
$3.91 | 
7% OFF MSRP:$4.20

In Stock

Outer Housing

#21

Boom and trimmer Diagram

Outer housing

Part #753-04304
?
Manufacturer substitution
This part replaces 753-04304. Substitute parts can look different from the original.
This part replaces 753-04304
$36.95

In Stock

Reel Line

#NI07

All parts Diagram

Reel line

Part #753-04218
?
Manufacturer substitution
This part replaces 753-04218. Substitute parts can look different from the original.
This part replaces 753-04218
$21.60

In Stock

Line Trimmer Motor Compression Spring

#87

Engine parts Diagram

Line trimmer motor compression spring

Part #791-612468
?
Manufacturer substitution
This part replaces 791-612468. Substitute parts can look different from the original.
This part replaces 791-612468
This item is not returnable
$6.79

In Stock

Lawn & Garden Equipment Engine Valve Cover Gasket

#5

Engine parts Diagram

Lawn & garden equipment engine valve cover gasket

Part #791-182099
?
Manufacturer substitution
This part replaces 791-182099. Substitute parts can look different from the original.
This part replaces 791-182099
This item is not returnable
$6.92

In Stock

Elastic Nut

#20

Boom and trimmer Diagram

Elastic nut

Part #791-181886
?
Manufacturer substitution
This part replaces 791-181886. Substitute parts can look different from the original.
This part replaces 791-181886
This item is not returnable
$2.66 | 
8% OFF MSRP:$2.90

In Stock

Showing 10 of 135 parts

Symptoms for gas line trimmers

Choose a symptom to see related grass line trimmer repairs.

Main causes: stale fuel, cracked fuel lines, dirty carburetor, bad spark plug, worn piston rings
Main causes: cracked fuel lines, bad carburetor seals, leaky fuel tank cap, damaged fuel tank
Main causes: stale fuel, clogged fuel filter, faulty spark plug, clogged air filter, cracked fuel lines, clogged carburetor

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.

October 1, 2013
By Lyle Weischwill
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 yourself, following these instructions.

Repair difficulty
Time required
 30 minutes or less
October 1, 2013
By Lyle Weischwill
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 these instructions to do the job in under 30 minutes.

Repair difficulty
Time required
 30 minutes or less
October 1, 2013
By Lyle Weischwill
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 instructions to replace the carburetor in under 30 minutes.

Repair difficulty
Time required
 30 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.

June 1, 2016

Tips for a hard-to-start grass line trimmer

By Sears PartsDirect staff

These tips may help you get your hard-to-start gas line trimmer running.

June 1, 2015

How to replace a line trimmer fuel line video

By Sears PartsDirect staff

Follow the steps in this video to replace a leaking fuel line in a line trimmer.

March 1, 2015

Easy DIY grass line trimmer repairs

By Sears PartsDirect staff

Learn about some very easy do-it-yourself repairs for a grass line trimmer.