Stupid Newbie Question

[jcarlberg]

Have a couple of saws now (390XP & MS 261). Is it difficult to remove the spark arrestor screens & can anyone point me to a step-by-step? I’ve poked around a bit but can’t find exactly what I’m looking for. Or should I be removing the mufflers & sending them off for mods (& if so, to whom?). Thanks!

 

[Loony661]

Have a couple of saws now (390XP & MS 261). Is it difficult to remove the spark arrestor screens & can anyone point me to a step-by-step? I’ve poked around a bit but can’t find exactly what I’m looking for. Or should I be removing the mufflers & sending them off for mods (& if so, to whom?). Thanks!

Why remove the screens? They really don’t inhibit flow much. I prefer them in all my saws for piece of mind.

 

[Ketchup]

Look for the screw on the muffler. It’s holding the back of the screen in a slot. It’s on top of the 390, PTO side on the 261. You won’t see huge gains removing them but it’s important to make sure they are clean. If you want to go after power gains you will need to make a second outlet. The simplest way to do that is get an aftermarket deflector and make a new hole. Pre-modded mufflers are also available online.

 

[ammoaddict]

Have a couple of saws now (390XP & MS 261). Is it difficult to remove the spark arrestor screens & can anyone point me to a step-by-step? I’ve poked around a bit but can’t find exactly what I’m looking for. Or should I be removing the mufflers & sending them off for mods (& if so, to whom?). Thanks!

Nice saws you picked out for a newbie.
Keep the screens in to keep foreign objects out. I have a saw without a screen, couple stink bugs got in there. Fried stink bugs don't smell good. If the need cleaning, take them out and burn them off with a propane torch, brush them off and put them back in.

 

[FederalQ]

I recently worked on a Husqvarna 41 (made by Poulan) for a buddy of mine and discovered the spark arrestor screen was encircled around the baffle/birdcage. I have not seen that before. So I gave the muffler an extra gill on the flywheel side.

 

[ammoaddict]

I recently worked on a Husqvarna 41 (made by Poulan) for a buddy of mine and discovered the spark arrestor screen was encircled around the baffle/birdcage. I have not seen that before. So I gave the muffler an extra gill on the flywheel side.

All those older little Poulans are like that. The definitely need a muff mod. I have a 41 as well. I drilled some bigger holes in the baffle and put another gill in front of the existing one. Good little saws.

 

[jcarlberg]

Why remove the screens? They really don’t inhibit flow much. I prefer them in all my saws for piece of m

Look for the screw on the muffler. It’s holding the back of the screen in a slot. It’s on top of the 390, PTO side on the 261. You won’t see huge gains removing them but it’s important to make sure they are clean. If you want to go after power gains you will need to make a second outlet. The simplest way to do that is get an aftermarket deflector and make a new hole. Pre-modded mufflers are also available online.

I’ve been running Aspen fuel but nearly out of it so looking at mixing (best I can get around here is 91 octane). After reading a bit I think I’m gonna go around 33:1 - but read that a downside of going rich is that the spark arrestor might get plugged (so thought I’d just remove it).

Also wondering whether I should use up the Stihl 2-stroke oil I have or get something “better.”

 

[Loony661]

I’ve been running Aspen fuel but nearly out of it so looking at mixing (best I can get around here is 91 octane). After reading a bit I think I’m gonna go around 33:1 - but read that a downside of going rich is that the spark arrestor might get plugged (so thought I’d just remove it).

Also wondering whether I should use up the Stihl 2-stroke oil I have or get something “better.”

If you run a quality oil, you won’t need to clean the spark arrestor. Quality oils burn clean and leave little to no deposits behind. I run all my saws at 32:1.

 

[jcarlberg]

If you run a quality oil, you won’t need to clean the spark arrestor. Quality oils burn clean and leave little to no deposits behind. I run all my saws at 32:1.

Great! Is Stihl 2-stroke a quality oil, or what should I use?

 

[FederalQ]

The Stihl 2T oil sold in Canada may be made by Castrol and would be fine to run. I use 91 E-free octane and mix 32:1 for large saws and haven‘t had issues with spark arrestor screens at all.

 

[Woodslasher]

One thing I do on my saws is make the muffler outlet hole the same size as the inside of the deflector. Does it make a huge difference? Maybe not, but on a 350 or 372 style Husky I'd say it doubles the size of the muffler outlet. Also, I always run screens. They're required to cut on gov't land in CA, and they keep bugs, mud dauber nests, etc out like others have stated.

 

[atpchas]

Have a couple of saws now (390XP & MS 261). Is it difficult to remove the spark arrestor screens & can anyone point me to a step-by-step? I’ve poked around a bit but can’t find exactly what I’m looking for. Or should I be removing the mufflers & sending them off for mods (& if so, to whom?). Thanks!

Below for the 261. The 390 user manual (available at stihlusa.com) should show something similar.

 

[HumBurner]

All those older little Poulans are like that. The definitely need a muff mod. I have a 41 as well. I drilled some bigger holes in the baffle and put another gill in front of the existing one. Good little saws.

You got one or both of them running?!?!?

 

[ammoaddict]

You got one or both of them running?!?!?

One. Runs pretty good.

 

[HumBurner]

One. Runs pretty good.

Awesome! I'm glad to hear it!

 

[jcarlberg]

Below for the 261. The 390 user manual (available at stihlusa.com) should show something similar.


View attachment 417738

Thanks!!

 

[Jake Dykstra]

Great! Is Stihl 2-stroke a quality oil, or what should I use?

Everybody has there favorite I would guess. Don't like the stihl oil personally because of the carbon build up. It has always seemed to be excessive with stihl oil.
My favorite is the VP oil at 40:1

 

[sawmikaze]

Why remove the screens? They really don’t inhibit flow much. I prefer them in all my saws for piece of mind.

This.

All mine are screened, muffles the sound too.