Solo
Gas Chainsaw

Model #644 Official Solo gas chainsaw

Here are the diagrams and repair parts for Solo 644 gas chainsaw, as well as links to manuals and error code tables, if available.

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For DIY troubleshooting advice and repair guides, visit our repair help section.

Showing 10 of 264 parts

15 Chain#180

Chain saw engine Diagram

Chain 13"

Part #6900908
Replaced by #21BPX056G
?
Manufacturer substitution
This part replaces 6900908. Substitute parts can look different from the original.
In Stock
$27.44
Chain, 16-in#180A

Chain saw engine Diagram

Chain 15"

Part #6900881
Replaced by #21BPX064G
?
Manufacturer substitution
This part replaces 6900881. Substitute parts can look different from the original.
In Stock
$31.31
BAR  15IN CO#175A

Chain saw engine Diagram

Bar 15"

Part #6900464
Replaced by #158PXLBK095
?
Manufacturer substitution
This part replaces 6900464. Substitute parts can look different from the original.
In Stock
$69.91
BAR  16IN VE#175B

Chain saw engine Diagram

Bar 15"

Part #6900343
Replaced by #160VXLGK095
?
Manufacturer substitution
This part replaces 6900343. Substitute parts can look different from the original.
In Stock
$59.24
Chain, 16-in#180B

Chain saw engine Diagram

Chain 15"

Part #6900875S
Replaced by #20BPX067G
?
Manufacturer substitution
This part replaces 6900875S. Substitute parts can look different from the original.
In Stock
$32.73
BAR  13IN CO#175

Chain saw engine Diagram

Bar 13"

Part #6900500
Replaced by #138PXLBK095
?
Manufacturer substitution
This part replaces 6900500. Substitute parts can look different from the original.
In Stock
$55.00
BAR 18IN VE (replaces 180SLGK095)#175C

Chain saw engine Diagram

Bar, 18-in

Part #6900861
Replaced by #180VXLGK095
?
Manufacturer substitution
This part replaces 6900861. Substitute parts can look different from the original.
In Stock
$63.44
Washer#11

Starter Diagram

Washer

Part #0031260

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

Circle Clip#81

Chain saw engine Diagram

Circle clip

Part #0055104

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

Screw#16

Handle bar Diagram

Screw

Part #0010512

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

Symptoms for gas chainsaws

Choose a symptom to see related chainsaw repairs.

Main causes: stale gasoline, cracked fuel lines, dirty carburetor, damaged spark plug, worn piston rings
Main causes: bad gas, engine needs tune up, cracked fuel lines, dirty carburetor
Main causes: cracked fuel lines, leaky carburetor seals, damaged fuel tank cap, cracked fuel tank

Repair guides for gas chainsaws

These step-by-step repair guides will help you safely fix what’s broken on your chainsaw.

How to rebuild a chainsaw carburetor

If your chainsaw isn't running well, a dirty carburetor could be the problem. You can take it apart, clean it and rebuild it, using a carburetor rebuild kit. This repair guide takes you through the process.

Repair difficulty
Time required
 15 minutes or less
How to replace chainsaw fuel lines

The fuel line on a chainsaw becomes brittle over time and can crack. Replacing it doesn't require a lot of DYI experience. These instructions show you how.

Repair difficulty
Time required
 15 minutes or less
How to replace a chainsaw carburetor

If the engine won't start even though there's fuel in the chainsaw, the carburetor could be the problem. Sometimes, it's easier to replace the carburetor than to clean it and rebuild it. Follow these steps to do the job yourself in about half an hour.

Repair difficulty
Time required
 15 minutes or less

Articles and videos common to all chainsaws

Use the advice and tips in these articles and videos to get the most out of your chainsaw.

July 12, 2022

What are the most common replacement parts for chainsaws?

What are the most common replacement parts for chainsaws?

Learn about the most common replacement parts for chainsaws and how they can help you fix chainsaw problems.

June 29, 2022

Top questions about Sears and Sears PartsDirect

Top questions about Sears and Sears PartsDirect

Get answers to frequently asked questions about Sears and Sears PartsDirect.