Infographic of FS 251 pointing out the Semi-Automatic Choke Lever, Vertically Pleated Paper Air Filter, Bike Handle, and TapAction™ AutoCut® 27-2 Trimmer Head

FS 251

Name: FS 251
Brand: STIHL
SKU: fs251
Rating: 5.0000 (2 reviews)

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This powerful gas trimmer is designed with an easy-to-adjust bike handle and a semi-automatic choke lever.

Features

Powerful Low Exhaust Emission Engine
STIHL ElastoStart™
TapAction™ AUTOCUT® Cutting Head
IntelliCarb™ Compensating Carburetor

Equipped with a simplified starting procedure, the FS 251 is a heavy-duty trimmer built for pros with no time to waste. Designed with a powerful low exhaust emission engine, the FS 251 saves on fuel and operating costs without losing any of the power. The FS 251’s easy-to-adjust bike handles provide comfort and ease while tackling widespread, overgrown areas. With a rugged design that offers optimal maneuverability and a vertically-pleated paper air filter that provides an extended service life, you can get to work quicker and count on the gas trimmer to last longer.

Note: Available for purchase in California with the 4-tooth grass cutting blade only.

Cutting Heads & Blades Selection Chart (PDF)

Features
- Powerful Low Exhaust Emission Engine -
  A powerful low exhaust emission engine saves users fuel and operating costs without losing the power they count on to get the job done.
- STIHL ElastoStart™ -
  The ElastoStart™ starter handle is a feature of STIHL. It is a starting grip with a built-in shock absorber that helps reduce the effort when pulling on the starter cord. The ElastoStart™ starter grip noticeably reduces the sudden peak forces (compression) normally felt during cranking. The forces which occur at the grip after the first compression stroke are smoothed out.
- TapAction™ AUTOCUT® Cutting Head -
  TapAction™ allows users to adjust the line length simply by tapping the cutting head against the ground.
- IntelliCarb™ Compensating Carburetor -
  The IntelliCarb™ Compensating Carburetor measures the air pressure on the clean side of the air filter and adjusts the metering diaphragm in the carburetor. This keeps the RPM at a consistent level, even when the air filter begins to clog.
- Bike Handle -
  When used in conjunction with a harness, the bike handle allows the machine to be easily guided, enabling a smooth horizontal mowing action to cover large areas quickly and efficiently. With soft grips for increased comfort, the bike handle provides greater control and helps reduce operator fatigue.
- Anti-Vibration System -
  STIHL has a system for minimizing the vibration levels of handheld outdoor power equipment. The STIHL anti-vibration system helps reduce operator fatigue and provides a more comfortable working experience.
- Shoulder Strap / Carrying System -
  Using a shoulder strap or carrying system helps distribute the weight of the equipment for increased operator comfort and improved maneuverability.
- Tool-Free Handle Adjustment -
  The central wing nut enables easy adjustment without the use of tools. For transportation and space-saving storage, the handle can be rotated 90°.
- Multi-Function Control Handle -
  Having easy access to all of the controls on one comfortable handle makes it easy to complete tasks so the operator’s hand never has to leave the handle.
- Semi-Automatic Choke Lever -
  The semi-automatic choke lever enables the simplified three-step start procedure, saving users time and allowing them to start jobs faster.
- Simplified Starting Procedure -
  To get started, users simply pump the fuel primer, set the choke, and pull the starter cord. The built-in stop switch allows the user to turn off the engine with a simple press of the button. When the engine is off, the throttle lock automatically returns to the "start" setting. The tool will be ready to start again when the user is ready to get back to work.
- Vertical Pleated Paper Air Filter -
  Thanks to better air filtration due to its greater surface area, the vertical pleated paper air filter can extend the time between servicing.
- Air Filter Cover -
  Easily remove the cover for fast and easy filter cleaning or replacement.
- Protected or Enclosed Control Cables -
  Dangling and loose wires are eliminated.
- Protected Spark Arrestor Muffler -
  Large baffles reduce noise level and contain a screen designed to reduce the emission of sparks.
- Protected Spark Plug -
  The spark plug is protected yet easy to change.
- Protected Choke Lever/Knob -
  The choke is protected to help prevent damage.
- High-Tech Polymer Housing -
  Housings are lightweight, withstand greater impact, and are corrosion-resistant.
- Heavy-Duty Steel-On-Steel Clutch -
  Centrifugal clutch is designed to reduce slippage.
- Purge Pump Primer -
  By pressing the bulb, this small fuel pump delivers fuel to the carburetor, reducing the number of starting pulls needed after an extended break between uses.
- Upright Translucent Fuel Tank -
  Easily check the fuel level before starting work. If fuel is needed, the upright position makes the tank easier to fill.
- Fully-Lined Drive Shaft -
  A lined shaft provides smooth operation and less vibration.
- Throttle Trigger Interlock -
  This safety feature must be depressed before the trigger can be activated.

Specifications

Questions And Answers

Reviews

Warnings And Safety
How to Wind a STIHL Trimmer Head - Video
Cutting Heads & Blades Selection Chart (PDF)
FS 251 Instruction Manual (PDF)
Product Safety Manual (PDF)
STIHL Limited Warranty
Contact Us
Note: STIHL recommends use of fuel with no more than 10% Ethanol content. Using fuel with greater than 10% Ethanol content may cause damage to your equipment and may void your STIHL warranty.
WARNING! Improper use of any trimmer/brushcutter can cause serious or fatal injury. Read, understand, and follow all safety instructions in your instruction manual. To reduce the risk of injury from blade contact, circular saw blades may be used on FS brushcutters that have a limitstop, a bicycle handle, and double shoulder harness and not on FS brushcutters with a "J" handle or loop handle. Other rigid blades may be used on FS brushcutters having a bicycle handle, a "J" handle, or a loop handle equipped with a barrier bar. To reduce the risk of eye injury always wear proper eye protection. Always use the appropriate deflector for the type of cutting attachment, as explained in your instruction manual.
WARNING! Improper use of any power tool may cause serious or fatal injury. Read, understand, and follow carefully the operating and safety instructions in your instruction manual before using such products.

STIHL products sold through U.S. STIHL Dealers are for distribution in the United States only.

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WEIGHT	15.2 lbs.
POWER SOURCE	Gas
CUTTING WIDTH	16.5 in.
ENGINE POWER	2.7 bhp
FUEL CAPACITY	25.4 oz.
DISPLACEMENT	41.6 cc