Stihl MS170 air filter modification

[LRT]

I’ve bought a lightweight Stihl MS170 saw to use for pruning and light cutting rather than using the heavy MS441.

After the first tank of fuel I removed the cover to check the spark plug condition and noticed the poorly designed airfilter is letting fine sawdust past the lip on the top cover that clamps over the filter. There is some in the intake as well.

Since I’ve only been using it to cut green wood the sawdust is minimal but is concerning if I were to use it on dry wood.

I’m thinking of finding some sort of rubber to glue onto the housing to provide a better seal. Or do I try and get a warranty on it?

 

[HarleyT]

Did you buy it new?

Can you snap a pic of the dirt/filter?

 

[1Alpha1]

If you bought it new, I'd take it back to the dealer and let them resolve the issue.

 

[walterg]

I've used a MS170 for 12 years and never had that problem on mine. So they have either changed the design slightly or...
Now, if your using an AM filter they don't fit as good as a Stihl filter.

Sent from my LGLS775 using Tapatalk

 

[HarleyT]

They have changed the air filter a bunch, which is why I was asking.

 

[Conquistador3]

Agree.

New: take it back to the dealership and let them sort it out.
Used: put a genuine Stihl filter on it.

 

[LRT]

Yes I bought it exactly a week ago today and have only used two tanks of fuel so far.

It has the original Stihl filter from purchase

I’m inclined to take it in rather than modifying it and finding it still leaks.

 

[LRT]

Some photos

 

[LRT]

I wonder if the filter from an MS171 is better? Stihl’s Australian website advertises that the 171 has a long life filter but it could be sales pitch to make you spend extra money.

 

[LRT]

This is the inside of the cover

 

[Conquistador3]

You can ask your dealership for a new air filter under warranty to see if it seals better, but it looks normal for an MS170.
Personally I wouldn't worry, but I am the guy who walked around 30+ years with a serious heart deformity before starting to think something was wrong.

 

[LRT]

Ok I’ll get a new filter and see if it keeps happening. I don’t like the idea of dirt getting in, especially on a new saw.

 

[anlrolfe]

This may sound strange but look at the brake handle...

My 017 / 180convert activating the chain brake would slightly lift the top cover. Look on the left side where is attaches to the frame next to the recoil starter. IIRC when the brake handle was snapped fully back to deactivate it they touched enough to lift and let in saw dust. Because my saw was used, my solution involved the dremel machine. I'll go get a pic and attach in another post.

 

[anlrolfe]

Brake handle forward , released, neutral position.



Brake handle pulled fully back to release brake. This used to lift the lid and let dust into the carb. I was never sure if this was natural occuring or because on my engine transplant w/ Chi-Con 180 equivalent.

 

[walterg]

I wonder if the filter from an MS171 is better? Stihl’s Australian website advertises that the 171 has a long life filter but it could be sales pitch to make you spend extra money.

The MS171 uses a flocked air filter. It seems to be a much better design and fit.
I have never used a MS171 so I don't know how they hold up to dirt infiltration.

Sent from my LGLS775 using Tapatalk

 

[HarleyT]

Here is the filter on the basic MS171.

 

[walterg]

Harley, to my understanding Stihl is now using the fleece flocked air filter on the MS171, MS181, and MS211.
I looked at a MS211 yesterday at my dealer and it was flocked. Wish I had looked at the MS171 but didn't.
All 3 saws use the same filter.

Sent from my LGLS775 using Tapatalk

 

[HarleyT]

The ms171s around here come with the filter I just put up. I bought this saw new a week or two ago.

 

[1Alpha1]

Yes, definitely return it to the dealer and let them sort out the issues. Ask them if there is an updated or upgraded filter for it?

 

[Cody]

Harley, to my understanding Stihl is now using the fleece flocked air filter on the MS171, MS181, and MS211.
I looked at a MS211 yesterday at my dealer and it was flocked. Wish I had looked at the MS171 but didn't.
All 3 saws use the same filter.

Sent from my LGLS775 using Tapatalk

The air filter is different between the 211 and the 171, the 211 filter is pictured below. The carburetor has a larger baffle plate so the flat air filter and cage from the 171 won't work on it. I've got a guy that dropped off a 211 and he would like the filter that the 171 has but I told him I don't think it'll work, and I don't feel comfortable removing the baffle plate and running it that way. I'm thinking about just ordering a handful of the 211 filters and running them on the 171 as well, looks to be a little less restrictive anyways but still enough filtering. Anybody with any insight on this?