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Stihl Gas-Powered Chainsaw Wood Boss, 18in. Bar, 45.6cc Engine, 0.325in. Chain Pitch, Model# MS 251

Item# 63876
186 of 1317 reviewers received a sample product or took part in a promotion
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Stihl Gas-Powered Chainsaw Wood Boss, 18in. Bar, 45.6cc Engine, 0.325in. Chain Pitch, Model# MS 251

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Stihl Gas-Powered Chainsaw Wood Boss, 18in. Bar, 45.6cc Engine, 0.325in. Chain Pitch, Model# MS 251

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$399.99
Reg $429.99Save $30.00

Order today to get this price.

  • Offer: FREE Double Warranty Coverage with Purchase of a Qualifying Stihl Tool and Select Engine Oil See Details

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    Available now

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  • 2.95 HP, 45.4cc engine delivers the power you need
  • 18in. bar with 0.063in. chain gauge and 0.325in. chain pitch
  • Electronic Ignition for easier starting and smoother running
  • Anti-vibration system minimizes vibration levels, helping to reduce operator fatigue and provide a more comfortable working experience
  • Reduced-Emission Engine Technology is environmentally conscious, producing zero or low exhaust emissions

See full description

Complete Your Solution

  • Stihl Gas-Powered Chainsaw Wood Boss, 18in. Bar, 45.6cc Engine, 0.325in. Chain Pitch, Model# MS 251
  • Stihl, HP Ultra "Fully Synthetic" 2 Cycle Engine Oil, 2.6 oz, 6-Pack, Model# 0781 313 8003
  • Stihl, HP Ultra "Fully Synthetic" 2 Cycle Engine Oil, 6.4 oz, 6-Pack, Model# 0781 313 8009
Price for all three:

$452.97

Frequently Bought Together

  • Description

  • Key Specs

  • Reviews

  • Q & A

  • Accessories

  • Warranty

  • Compare

Product Summary

This Stihl Wood Boss® Gas-Powered Chainsaw is designed to deliver exceptional power with a comfortable and ergonomic design. It's the perfect choice for felling small trees, pruning and thinning, and cutting firewood simply and efficiently. And with up to 20% fuel savings and 50% reduced emissions (as compared to previous Stihl chainsaw models), you can enjoy longer run times with less impact on the environment.

What's Included

    (1) Stihl Wood Boss Chainsaw -- 18in. Bar, Model# MS 251

Features + Benefits

  • 2.95 HP, 45.4cc engine delivers the power you need
  • 18in. bar with 0.063in. chain gauge and 0.325in. chain pitch
  • Electronic Ignition for easier starting and smoother running
  • Anti-vibration system minimizes vibration levels, helping to reduce operator fatigue and provide a more comfortable working experience
  • Reduced-Emission Engine Technology is environmentally conscious, producing zero or low exhaust emissions
  • Tool-less fuel and oil caps with retainers allow you to simply lift the lever and twist the caps to remove or tighten -- no tools necessary
  • Master Control Lever? is an easy to use single lever which operates the choke, starting throttle lock and on-off switch
  • As an authorized STIHL dealer, Northern Tool + Equipment provides in-store service and warranty support for STIHL gas-powered equipment shipped directly to you. For return inquiries, please contact Customer Care for assistance.

Key Specs

AttributeSpecification

item#

63876

Brand

Stihl

Manufacturer's Warranty

1 year limited warranty

Ship Weight

5.85 LB

Bar Length

18 in

Engine Displacement

45.6 cc

Chain Pitch

0.325

Fuel Capacity

13.2 oz
AttributeSpecification

Power Type

Gas

Horsepower

2.95

Case Included

No

Oil Capacity

6.7 oz

Oil Fuel Mix Ratio

50:1

Low Vibration Handle

Yes

Tool-Less Chain Tensioning

No

Product Weight

10.8 lb

Reviews

Questions & Answers

1317 Reviews This action will navigate to reviews.

Questions

1–9 of 9 Questions  
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  1. Will a 20” bar work with this saw

    1 answer

    1. Sihl recommends only the use of a 12-18 inch bar on the model MS 251 Wood Boss chainsaw.

      Helpful?

  2. how do you change the chain on the saw?

    1 answer

    1. Step-by-Step: Replacing the Chain on a Stihl MS 251
      1. Ensure the Saw Is Off and Cool

      Engage the chain brake (push it forward).

      Let the saw cool down completely if it was recently used.

      Disconnect the spark plug boot for added safety.

      2. Remove the Side Cover

      Use your scrench or a socket wrench to loosen the two nuts on the side cover (right side of the saw).

      Remove the clutch cover carefully — the chain brake is inside it, so don’t force it.

      3. Release the Chain Tension

      Turn the chain tensioner screw counterclockwise (located between the nuts or on the side, depending on version).

      This loosens the chain so it can be removed easily.

      4. Remove the Old Chain

      Slide the guide bar slightly back toward the saw.

      Carefully lift the chain off the sprocket and the bar groove.

      5. Install the New Chain

      Position the new chain onto the sprocket first (behind the clutch drum).

      Lay the chain into the bar groove, making sure the cutting teeth face forward on the top side of the bar.

      The sharp cutting edges should move away from the saw on the top, and toward the saw on the bottom when rotating.

      Reinstall the Side Cover

      Replace the side cover over the bar studs and lightly hand-tighten the nuts.

      Make sure the tension adjuster pin lines up with the hole in the bar.

      7. Adjust Chain Tension

      Turn the tension screw clockwise until the chain snugly fits in the bar groove but can still be pulled around by hand.

      You want about 1/8 inch of give when lifting the chain in the middle of the bar.

      8. Tighten the Bar Nuts

      Once the tension is correct, tighten both bar nuts firmly with the scrench.

      9. Final Check

      Release the chain brake.

      Make sure the chain moves freely around the bar when pulled by hand (wear gloves!).

      Check the tension again after a short use — new chains stretch and may need a second adjustment.

      Helpful?

  3. Does the Wood Boss come in a box and or storage case?

    1 answer

    1. This chain saw does not include a case; however, item 99582 would work.

      Helpful?

  4. Can you use a rip chain on this model? Does Stihl make a 18" ripping chain?

    1 answer

    1. A ripping chain could be used on this saw. Northern Tool does not carry any Stihl ripping chain.

      Helpful?

  5. Dose the still wood boss 18in come with a chain?

    1 answer

    1. This chainsaw will include the chain.

      Helpful?

  6. Does this one have the easy pull starter?

    1 answer

    1. The Stihl MS 251 has an easy pull starter.

      Helpful?

  7. Does the chain have automatic oiler

    1 answer

    1. The chainsaw would have an automatic oiler.

      Helpful?

  8. Whats the difference between the wood boss & the 251c- be dont know what the be stands 4

    1 answer

    1. The C-BE model is equipped with a quick chain adjuster and easy start, these features are not included on the MS 251.

      Helpful?

  9. EZ start?

    0 answers

Accessories We Recommend

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Warranty

Manufacturer's Warranty

1 year limited warranty

Extend Your Warranty Coverage with a Northern Protection Plan (NPP)

Replacement Plan — 1 Year

A Northern Protection Plan is available after adding the product to your shopping cart.

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Stihl Gas-Powered Chainsaw Wood Boss, 18in. Bar, 45.6cc Engine, 0.325in. Chain Pitch, Model# MS 251
4.4 out of 5 stars. 1317 reviews
186 of 1317 reviewers received a sample product or took part in a promotion

Stihl Gas-Powered Chainsaw Wood Boss, 18in. Bar, 45.6cc Engine, 0.325in. Chain Pitch, Model# MS 251

Item # 63876

$399.99
Reg $429.99Save $30.00

Order today to get this price.