MS 251 WOOD BOSS®


18 in. Bar

A powerful and fuel-efficient chainsaw that’s comfortable to use.

The STIHL MS 251 WOOD BOSS® Chainsaw is powerful, fuel-efficient and easy to use. Ergonomically designed to bring you maximum comfort during use, this tool produces 50 percent less emissions (as compared to previous models) for a smaller impact on the environment. The MS 251 WOOD BOSS® packs features like a Master Control Lever™ and easy-to-refill fuel and oil tanks, so you can worry less about st...Read More
Print Spec Sheets
MS 251 WOOD BOSS® Specifications
DISPLACEMENT 45.6 cc (2.78 cu. in.)
ENGINE POWER 2.2 kW (2.95 bhp)
POWERHEAD WEIGHT 4.9 kg (10.8 lbs.)
FUEL CAPACITY 390 cc (13.2 oz.)
CHAIN OIL CAPACITY 198 cc (6.7 oz.)
OILOMATIC® CHAIN .325" RM3
GUIDE BAR LENGTHS* (Recommended ranges) 40 to 45 cm (16" to 18")
STIHL ROLLOMATIC®
POWER SOURCE Gas
STIHL recommends #3634 (26 RM3 68) OILOMATIC® saw chain and 18" 3005 008 4717 STIHL ROLLOMATIC® E guide bar combination. The actual listed guide bar length can vary from the effective cutting length depending upon which powerhead it is installed.
Model Features
  • Zoom
    Reduced-Emission Engine Technology - Caring for Nature
    The STIHL Inc. “Caring for Nature” seal identifies its powered products that are more environmentally conscious, producing zero or low exhaust emissions. STIHL Inc. defines “low exhaust emissions” as being cleaner than EPA and/or CARB exhaust emission standards.

    More Information

  • Zoom
    Toolless fuel and oil caps with retainers
    Simply lift the lever and twist the caps to remove or tighten. There‘s no need to use a tool to tighten or loosen.
  • Zoom
    Master Control Lever™
    The Master Control Lever™ is an easy to use single lever, operating the choke, starting throttle lock and on-off switch. The operator must pull the throttle trigger before moving the Master Control Lever™ to the choke position.
Standard Features
  • Zoom
    Common Features for Chainsaws
    View the features common to many STIHL chainsaws.

Important Information
* The actual listed guide bar length can vary from the effective cutting length based on which powerhead it is installed on.
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.
Click to view the STIHL Limited Warranty Time Periods
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    •2.6 oz. bottle makes 1 gallon mix

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    STIHL recommends a mix of 50:1 high-quality 89 octane or higher unleaded gasoline to STIHL engine oil. This same mix ratio should be used during break-in.

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    Bar and Chain Oil
    STIHL Bar and Chain oil is formulated to adhere to the bar and chain, and to reduce wear. Special agents in the oil formulation help keep sap and pitch from clinging to the bar and chain.

    Available in quart and gallon bottles, 5 gallon pails and 55 gallon drums, in both summer and winter weights.

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  • Complete Filing Kits Zoom
    Complete Filing Kits
    Kits available for the following chain types: STIHL PICCO Mini; 1/4" pitch chain; .325" pitch chain; 3/8" pitch chain; .404" pitch chain.
    Includes file guide, depth gauge, round file, flat file and two file handles in tool pouch.
    Chain Pitch File Diameter File Guide
    Part Number
    Sharpening Kit
    Part Number
    in. mm in. mm Part Number
    3/8 PMN 9.32 5/32 4.0 0811 411 8073

    5605 750 4327

    5605 007 1026

    1/4
    3/8 PM
    6.35
    9.32
    5/32 4.0 0811 411 8091

    5605 750 4327

    5605 007 1027

    0.325 8.25 3/16 4.8 0811 412 8088

    5605 750 4328

    5605 007 1028

    3/8 9.32 13/64 5.2 0814 243 3384 5605 750 4329

    5605 007 1029

    0.404 10.26 7/32 5.5 0811 412 8108 5605 750 4330

    5605 007 1030

For Your Safety
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    Woodcutter Chaps
    Apron Chaps from STIHL are made from rugged, 400-denier nylon and feature the same UL® classified protection as our other chaps. Just snap them over your pants and you’re ready to go. Sewn into the legs of the chaps are six layers of Avertic® Pro by Engtex®, a cut-retardant material designed to clog the sprocket and stop the saw chain on a gasoline-powered chainsaw in case of accidental contact with the rotating saw chain. The open back design of these chaps makes them a great choice for hot working conditions.
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    Woodcutter Helmet System
    The lightweight STIHL Woodcutter Helmet System is an excellent choice for budget-conscious non-professional users with chainsaws and pole pruners. Designed for comfort, the vented shell provides cooling air during use, and the 6-point mount suspension provides comfortable support. The STIHL Woodcutter Helmet System is Class G certified and includes NRR 22 hearing protection.
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    STIHL HomeScaper Series™ Gloves
    Innovative keyed thumb stitching for super comfort and gripping ability. Sizes available S, M, L, XL.

STIHL Dealer Days are Happening Now!

MS 251 WOOD BOSS® is rated 4.4 out of 5 by 215.
Rated 5 out of 5 by from Very good saw for the price Used it to take down five good size trees over the weekend. Easy to start and I found the saw very reliable. Maintaining the saw was just as easy as other brands I own. The dealer that I purchased the saw from was great, they filled out and sent in the warrantee paper work on my behave.
Date published: 2017-04-18
Rated 5 out of 5 by from Great Chainsaw Chainsaw starts up easy, and is light enough to run all day. Great saw for the money
Date published: 2017-04-17
Rated 5 out of 5 by from Excellent saw. I buy another one in a heartbeat. Starts easy. Doesn't stall. Great product. Starts easy. Doesn't stall. I've got the manual chain adjust feature. Very easy to work with. Reliable. Cuts great. Easy to work with and handle. Would buy another one in a heartbeat.
Date published: 2017-04-17
Rated 5 out of 5 by from Great purchase I bought into a 5-acre nut-tree farm, and had to clear some of the dead trees. This saw made short order of the trees I needed to thin, most between 3" and 10" diameter. I initially had trouble starting it on my own, then watched one of the handy Stihl videos, which prompted me to listen for the engine turnover before moving the starting switch. Have had no trouble with starting every time after that. Easy to fill gas and chain lube. Unbelievable cutting power.
Date published: 2017-04-17
Rated 5 out of 5 by from At 70 I'm back At 70 years old ,it fun again to get the work done . Very easy to start , dependable ,and useing a chain # 26RS /68 throws those wood chips , I'm a older Farmer now and now I look forward to going to the wood lot . In my 50 years of cutting wood I'm happy camper , indeed .
Date published: 2017-04-15
Rated 5 out of 5 by from Love this saw This thing is great starts easy and made fast work of cutting down and chopping up ten decent sized trees on my property
Date published: 2017-04-14
Rated 5 out of 5 by from Awesome saw for home or small ranch Starts easy plenty of power and low vibration. Extremely happy with this saw
Date published: 2017-04-14
Rated 5 out of 5 by from This product cuts nice! The first time I used the saw, I made maybe 40 cuts in 15 minutes!
Date published: 2017-04-13
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