Carburetor for Stihl MS231 MS231C MS251 MS251C – 1143 120 0611

Description

This Winzor aftermarket carburetor fits selected Stihl MS 231 and MS 251 series chainsaws. It replaces OEM 1143 120 0611 and follows the Zama C1Q-S295 carburetor pattern. Therefore, it offers a practical replacement for a worn, blocked or damaged original carburetor.

Compatible models

• Stihl MS 231
• Stihl MS 231 C
• Stihl MS 231 C-BE
• Stihl MS 251
• Stihl MS 251 C
• Stihl MS 251 C-BE

However, Stihl used several carburetor versions during production. Therefore, check the OEM number, carburetor markings and physical layout before ordering.

OEM and carburetor references

• Primary OEM number: 1143 120 0611
• Unspaced reference: 11431200611
• Earlier related reference: 1143 120 0605
• Later related reference: 1143 120 0641
• Carburetor type: Zama C1Q-S295
• Related marking: C1Q-S295A

Use the OEM references as comparison numbers because different production versions may require different carburetors.

Product details

• Product type: complete diaphragm carburetor
• Brand: Winzor
• Application: petrol chainsaw
• Engine type: two-stroke
• Carburetor pattern: C1Q-S295 type
• Condition: new aftermarket replacement part

A worn carburetor can cause difficult starting, unstable idling, hesitation or poor acceleration. In addition, blocked internal passages may cause fuel starvation or excessive fuel delivery. Replacing the complete carburetor can consequently provide a simpler solution than rebuilding a heavily worn unit.

Check compatibility before ordering

Before ordering, compare the 1143 120 0611 OEM reference with the number on your original carburetor. Also compare the mounting holes, fuel connections, choke mechanism, throttle linkage and adjustment-screw positions.

Some MS 231 and MS 251 chainsaws use a different WTF-series carburetor. Therefore, the chainsaw model alone does not guarantee compatibility. Use the product photographs and original carburetor as your main references.

Installation and adjustment

After installation, inspect the fuel lines, impulse passage, intake connection and fuel filter. Air leaks or restricted fuel flow can produce symptoms similar to carburetor failure.

Next, start the chainsaw and check the idle speed, acceleration and fuel mixture. The carburetor may require final adjustment to suit the engine and local operating conditions. Incorrect adjustment can make the engine run lean and damage the piston or cylinder. Therefore, ask a qualified small-engine technician to tune it if you are unsure.

The package contains only the components shown in the product photographs. Gaskets, fuel lines and mounting hardware are not included unless the photographs show them.

Stihl and Zama names and part numbers identify compatibility only. This product is an aftermarket replacement and is not manufactured by those companies.