When buying a chainsaw, it’s safe to say that you would want to include the Stihl MS 311 and MS 391 chainsaws among your choices, as they are the top models on the market. When choosing between these two, you will be tempted to buy both, as they both have incredible qualities.
Now, the Stihl MS 311 and MS 391 have a variety of differences between them, in terms of engine power, bar length, displacement, and carburetor, among a few others. However, they are excellent choices.
Of course, we can’t overlook the features that make them unique, such as incorporating a decompression valve on the MS 311.
While deciding between one of them can be quite complicated, this guide will cover and evaluate the best aspects of both so you can make the best suitable decision for you.
- Pro: Powerful cutting capability
- Pro: Long cutting bar
- Pro: Greater tank capacity
- Pro: Excellent fuel economy
- Pro: Outstanding power-to-weight ratio
- Pro: Anti-vibration system
MS 311 vs MS 391: Quick Overview
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Stihl’s engine technology is recognized for reduced emissions, low fuel consumption, and longer run times in this high-powered chainsaw. In 2009, the Stihl MS 391 and the Stihl MS 311 went into production.
The MS 391 incorporates the latest engine technology that adds fuel efficiency while reducing emissions compared to other models.
Although 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 designed for big jobs on fields, farms, and ranches.
So if you want to cut down trees and firewood and clean up after the storm, it’s much easier to do those jobs with the rugged MS 391. If we compare the specs of the 311 and 391, we see that the 391 appears to be a superior chainsaw.
Both weigh the same, as mentioned in the description above, but the 391 will give you significantly more power.
Stihl MS 311 Overview
- Pre-separation Air Infiltration System
- Powerful cutting capability
- long cutting bar
- Greater tank capacity
- Fairly heavy
- Not environmentally friendly
If we talk about the MS 311, it is undoubtedly a technological workhorse with more performance and power than the MS 391. Thanks to these qualities, you can drive your vehicle for longer with less gasoline, thanks to its improved engine technology.
Add to that, that the MS 311 has larger oil and gasoline tanks for even longer continuous use. While you save money on gas, you’ll still be productive.
Thanks to the MS 311’s powerful, energy-efficient motor, you’ll spend less time idling while you work as you’ll achieve your goals more smoothly and quickly. For this reason, by increasing the efficiency of the engine’s filter system, this technique doubles the interval between air filter cleanings.
Before being sent to the air filter, the air drawn into the engine is initially divided by centrifugal force, which expels the heaviest dirt particles. Due to the pre-separation, the air filter has to be cleaned and consolidated less frequently because it can accumulate less dirt.
Unlike the usual bar adjustment screw position, the side access chain tensioner makes it much more convenient for the operator to adjust the chainsaw chain using a bar wrench.
Stihl MS 391 Overview
- Excellent fuel economy
- Outstanding power-to-weight ratio
- Anti-vibration system
- No decompression valve
- Hard to start
This powerful chainsaw uses STIHL engine technology, resulting in lower fuel consumption, longer run times, and lower emissions.
As has been repeatedly mentioned, this current engine technology has the advantage with which it increases fuel efficiency and reducing emissions compared to other models and is featured in the MS 391.
For this reason, it could be said that despite its comparable weight, the MS 391 is more powerful than the MS 311. Combining these factors with an ideal power-to-weight ratio, this is a chainsaw that is suited for huge tasks in the field, farm, and ranch.
With the robust MS 391, clearing weeds, chopping firewood, and clearing up storms just got a whole lot easier.
Stihl MS 311 vs Stihl MS 391: The comparison
Now comes the most important part, we will review the main differences in detail and focus our effort on concluding which of these two chainsaws is superior and the best suitable option for you.
Bar Size
Although there is never a perfect bar length for a particular saw, there is always a desirable length. The suggested lengths for the MS 391 and MS 311 chainsaws are very different.
Stihl claims that 16 inches are the best bar length to utilize with the 311 models. On the other hand, Stihl strongly suggests using 20-inch bars with the MS 391 saw. It’s crucial to remember that bars often cost more the longer they are.
Horsepower
Engine power is always an important attribute to consider because they must have strength and power to fell the strongest trees. However, the difference in power between the 311 and 391 may not be major, but it is noticeable.
The engine power of a 311 chainsaw is limited to 4.2 hp. On the other hand, the 391 chainsaws receive a slight increase of 0.2, giving it a 4.4 horsepower engine.
While it is true that the difference is not very significant, sometimes the extra power can really come in handy, especially when trimming tree stumps.
Displacement
One aspect not taken into consideration by most traditional loggers is engine power or the contemporary definition of power. Displacement is a phrase used to describe the power of a chainsaw.
Again, Stihl 391 chainsaws are the best in another respect. Compared to its rival, it has a displacement of 64.1 ccs.
Compression Release Valve
The decompression valve is one of the most desirable and necessary aspects of the 311 chainsaw. It vents cylinder pressure more effectively than ever before.
This will start your chainsaw faster, and you will experience fewer starting-related problems due to the decompression valve.
Surprisingly, the MS 391 chainsaws did not include this excellent feature despite their flexibility.
Compensation Carburetor
One important thing is that if the engine is not kept within a certain RPM range determined by the air filter, your chainsaw will not perform at its best.
Now, the IntelliCarb compensating carburetor includes a device that automatically modifies the air/fuel ratio as needed. Because of this carburetor, your chainsaw will not have any problems caused by air filters. On the other hand, it also prevents the filter from getting dirty.
A Stihl 391 chainsaw comes with a compensating carburetor. Unfortunately, this functionality is not accessible for Stihl 311 chainsaws.
Weight
If we talk about weight, both models of Stihl chainsaws feature the same weight, which is 13.67 pounds. Despite this, the Stihl 391 is appreciated with superiority over the 311 due to its power.
Fuel Capacity
The refueling process is not a problematic factor of the Stihl 311 and 391 models. Therefore, the frequency with which you should fill the tank depends on the fuel capacity.
Both models have a large fuel tank holding up to 20.3 ounces of gasoline. In addition, these chainsaws are capable of holding the same amount of chain oil (11.8 oz.).
Air Filter
One factor that we cannot forget to take into account in power tools is that these chainsaws come with an air filtration system upstream.
This prevents the air filter from accumulating dirt, so it doesn’t clog as quickly. Less dirt equals less frequent filter cleaning, which saves time.
Stihl MS 311 vs Stihl MS 391: Which one is the best?
Now that we’ve thoroughly compared both models, it’s time to decide which of the two is the best. The Stihl 311 chainsaw is fantastic with a decompression valve, short bar length, and good power. However, for a variety of reasons, I would not recommend it over the 391.
In terms of power and engine displacement, the MS 391 chainsaw is superior. The simple fact that the chainsaw maintains the same weight as the 311 versions while generating more power is truly amazing.
The Stihl 391 chainsaw further cemented our belief that it would always be the better choice thanks to extra features like the compensating carburetor. The MS 311 and MS 391 chainsaws clearly have several notable differences between them.
We believe that the 391’s strength will often be beneficial for heavy tree cutting. Meanwhile, the decompression valve and reasonable price of the 311 chainsaws may appeal to a wider audience.
Jake is a chainsaws expert with a wealth of knowledge and experience in the field. He is a licensed professional by the National Chainsaw Program, which attests to his skills and expertise in the safe and efficient use of chainsaws.
