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MS 391

MS 391
Our top-of-the-line chainsaw for farm and ranch.

Product Description

STIHL engine technology means low fuel consumption, longer run times and reduced emissions in this high-powered chainsaw. The MS 391 features our newest engine technology that adds fuel efficiency while reducing emissions as compared to other models. Though equal in weight, the MS 391 is more powerful than the MS 311. Add to that an optimal power-to-weight ratio and you have a chainsaw that’s cut out for the big jobs in field, farm and ranch. Felling trees, cutting firewood and cleanup after the storm just got a whole lot easier with the rugged MS 391.

Model Features

  • 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

Specifications

DISPLACEMENT
64.1 cc (3.9 cu. in.)
ENGINE POWER
3.3 kW (4.4 bhp)
POWERHEAD WEIGHT
6.2 kg (13.67 Ibs.)
FUEL CAPACITY
600 cc (20.3 oz.)
CHAIN OIL CAPACITY
350 cc (11.8 oz.)
OILOMATIC® CHAIN
3/8" RS3
GUIDE BAR LENGTHS* (Recommended ranges)
40 to 50 cm (16" to 20")
STIHL ROLLOMATIC®
POWER SOURCE
Gas
STIHL recommends #3624 (33 RS3 72) OILOMATIC® saw chain and 20" 3003 008 8921 Ematic™ guide bar combination. The actual listed guide bar length can vary from the effective cutting length depending upon which powerhead it is installed.

Important Information

WARNING! The occurrence called “kickback” can cause serious or fatal injury. Always read the instruction manual carefully before using your saw. STIHL uses a green and yellow color-coding system to help you select a powerhead, bar and chain combination that complies with the kickback requirements of ANSI Standard B175.1 (gasoline-powered saws) and §30 of UL 1662/ ANSI Standard B175.1 (electric chainsaws). Ask your STIHL dealer about safe operating procedures and the advantages of the STIHL Quickstop® chain brake, STIHL Quickstop® Plus (Q) additional chain braking feature, STIHL reduced kickback bars and STIHL low-kickback saw chains.

STIHL recommends the use of green reduced kickback bars and green low kickback chains on all STIHL chainsaws.

* The actual listed guide bar length can vary from the effective cutting length based on which powerhead it is installed on.

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. Learn More…

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.

Reviews

MS 391 is rated 4.5 out of 5 by 242.
Rated 5 out of 5 by from This saw lives up to my expectations, I have been a chain saw user since the 1960's And a stihl saw user since the late 1960's. Starts easy, adequate power for my use, easy maintenance, and dependable.
Date published: 2017-09-20
Rated 5 out of 5 by from Well thought out design. This saw has many little features that make it very user friendly and easy to maintain. From the single control lever for starting and running, to the laser etched reference guides on the chain, and the air bypass for preheated air for cold operating temperatures. I have blocked 20+ cords of pine with this saw so far and I have had no issues to date.
Date published: 2017-09-06
Rated 5 out of 5 by from Excellent saw in every way. Starts right-a-way every time, cuts fast and clean, well balanced, easy access for maintenance and cleaning. I mainly cut 16 to 24 inch pine logs and the saw cuts through quickly without bogging.I highly recommend the MS391.Mike
Date published: 2017-07-14
Rated 5 out of 5 by from INSANE POWER so I'm 12 years old and I ran this chainsaw for the first time more powerful than any Husqvarna I ran this thing is overpowered and excellent for what I need it for this is an insane saw it cuts fast I love it not even broken in yet and its still a champ.
Date published: 2017-07-13
Rated 5 out of 5 by from This makes retiring my old saw easy very pleased with my purchase Typical of all Stijl products they just run and so reliableMakes the work fun and quickOver all if you want a saw that you can pick up for a day of cutting or a hour or minutes get this saw as I find excuses to use it!
Date published: 2017-06-23
Rated 5 out of 5 by from Saw is a beast Put it to work for about 3 hours the first day. Cut through large trees like butter. Wish I would have bought a Stihl years ago.
Date published: 2017-06-16
Rated 2 out of 5 by from Unreliable Used this saw about 40 hours over two years before it quit starting. Starting it progressively got harder. Took to Stihl service center only to find out the ignition module is faulty. Bought one from Ebay and it still starts no easier. At least I have spark at the plug now but with arthritis I cannot pull it hard enough to start. I would think Stihl should last more than 40 hours before having to replace pricey parts.
Date published: 2017-06-08
Rated 4 out of 5 by from Quality built Product I am comparing this product to a 35 year old Pro Mac 700, so this may or may not be a fair comparison. A little disappointed in the power for a larger saw, had the 25" bar and chain installed at the dealer before purchase. Once its running, its a smooth cutting saw. Have run several tanks of gas thru it now, and am a little surprised at how finicky is is to start, especially after a warm refuel. Like the one quarter turn caps on the fuel tank and the oil tank, and the foot hole on the rear handle.
Date published: 2017-06-07
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Standard Features

  • Pre-Separation Air Filtration System
    This time-saving technology boosts the efficiency of the engine’s filter system, doubling the time between air filter cleanings. Air drawn into the engine is first separated via centrifugal force, ejecting the heavier dirt particles before being routed to the air filter. This pre-separation means less dirt to be captured by the air filter, resulting in less frequent cleaning and maintenance.

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  • Anti-Vibration System
    STIHL has developed 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.
  • IntelliCarb™ Compensating Carburetor
    The IntelliCarb™ Compensating Carburetor is designed to automatically adjust the air/fuel ratio when the air filter becomes restricted or partially clogged and maintains the engine’s correct RPM. IntelliCarb™ uses air from the clean side of the air filter to control the diaphragm and flow of fuel. As the air filter becomes dirty and less air is available for the carburetor, the IntelliCarb™ system adjusts the fuel flow to compensate for the decrease in air flow. This is in contrast to typical carburetors that utilize this air from the “dirty” side of the air box.
  • Side-Access Chain Tensioner
    The side-access chain tensioner makes it much more convenient for the user to adjust the saw chain with a bar wrench as opposed to the typical location of the guide bar adjustment screw.
  • Common Features for Chainsaws
    View the features common to many STIHL chainsaws.
  • 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.

You Will Also Need

For Your Safety

Support

Chainsaw Safety and Maintenance - Video
Product Instruction Manual (PDF)
Product Safety Manual (PDF)
STIHL Limited Warranty
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