Today, we’re going to be going through how to tighten Stihl chainsaw chain.
One thing we have to pay close attention to is the tension of our saw chain. As the saw is being used, the chain will have a tendency to loosen up. So, it’s very important that we check our chain tension often.
Why Tighten the Chain
Not only does a loose chain cause damage and premature wear to the chain itself, but it also causes damage to the sprocket and the bar.
So, I’m going to show you how quick and easy it is to tighten your Stihl chainsaw chain properly.
How to Tighten Stihl Chainsaw Chain
Here we have a steel MS 271 with a side access chain tensioning. This is where your scrench or a flathead screwdriver to adjust the tension.
A lot of people ask what a scrench is. It’s a tool with a screwdriver to tension the chain. It’s got openings on the other end to tighten the bar nuts and sometimes even an opening to tighten the plug.
On this Stihl MS 170 the chain tensioner screw is located in the front of the saw. Sometimes, the tensioner can be on the inboard side of the bar and sometimes on the outboard side, depending on the chainsaw you have.
On this Stihl MS 211 C, there’s a quick chain adjuster. With this style, no tools are needed to make the adjustments.
With the side cover removed, you’ll see the adjustment pin. This pin engages the bar and moves forward and backward depending on if you need to tighten or loosen the chain tension.
On the bar, there’s several openings. Stihl bars are designed so the bar can be mounted on either side. That’s important because you want to turn the bar over to distribute the wear evenly on both sides resulting in longer life of the bar.
Stihl recommends that you do this every time you replace or sharpen the chain.
The small holes are where the bar and chain oil is channeled to the inside of the bar rails.
This is the hole where the adjustment pin needs to line up. Anytime you loosen or remove the side cover, make sure the pin is aligned with the hole before you put the cover back on or you can severely damage the saw.
When installing or replacing the chain, it’s easiest if you adjust the pin to the loosest position or all the way back.
Place the chain on the bar and then over the sprocket. Make sure the drive links fit correctly with the sprocket. Position the bar where to fit securely on the bar studs and the adjustment pin is lined up with the proper hole in the bar.
Double-check that the pin is aligned in the adjustment hole on the bar and then place the side cover on the saw.
Tighten the nuts or the quick chain adjuster depending on what style you have, but only hand tight.
You still want to have some play up and down on the bar. If it’s too tight, you won’t be able to make the necessary adjustments.
Now, let’s talk about chain tension adjustment.
There are two different scenarios that we can consider, a cold chain that hasn’t been run for a while and a hot chain that has just been used.
Loosen the bar nuts just enough to where the bar has up and down play. Then, start tensioning the chain by rotating the adjustment screw clockwise. Adjust it to where the chains tie straps just touch the bottom of the bar rail.
Now, this is really important. Bars have a slight amount of movement up and down. To finish the adjustment process, you need to hold the tip of the bar up.
When you do this, you’ll see that the chain once again has slack in it. While holding the tip of the bar up, continue to tighten the chain until it’s snug against the bottom bar rail.
Still holding the tip of the bar up, tighten the bar nuts, then pull down on the chain. It should snap back up to the bottom bar rail.
Next, with both hands, rotate the chain around the bar. The chain should move freely with little effort.
If it doesn’t, loosen the bar nuts and take a little tension off the chain then tighten and repeat the process of checking the tension.
With a little practice, this will become very easy and instinctive. In the end, you’ll want the chain to be snug on the bottom rail but loose enough that it will rotate freely around the bar.
So, that’s the procedure for adjusting a cold chain, one that hasn’t been used.
The adjustment for a chain that you just finished cutting with, that’s a little different.
After you’ve just finished cutting with the saw, you can see the chain is hanging slightly below the bar rail, but the drive links are still well within the bar groove.
Hot chains stretch due to the heat and that’s normal. As the chain begins to cool down, you’ll see how it tightens up again.
So, if you were to tighten this chain while it is hot, then you are going to stop work long enough for the chain to cool down, which doesn’t take very long. Otherwise, you’ll end up with a chain that’s overly tight and this could damage the saw.
In this case, where you’ve been using the saw and the chain is slightly loose, this is normal and you should continue using the saw as it is.
But on the other hand, if it’s loose enough where the drive links are close to coming out of the bar rail as in the picture below, you should stop using the saw, let it cool down, and then readjust the chain.
One last thing, when you’re done working, loosen that chain. Storing a chainsaw with a tight chain can cause damage to the carrying shaft and the bearings.
Now, you know how to tighten Stihl chainsaw chain the proper way.
See you on the next one.