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Stihl 021-025/MS210-MS250 Muffler Mod

Discussion in 'Chainsaws and Power Equipment' started by MasterMech, Jan 15, 2015.

  1. MasterMech

    MasterMech The Mechanical Moderator

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    These saws are like fleas on a dogs back all across the country. Just a humble homeowner class clamshell saw but they are out there cutting up storm damage and putting up firewood everyday. Great power for the weight IMO, especially the 025/MS250. But there is a bit more that's pretty easily had from these little guys.

    First, a stock 1123 series muffler, this one is from a late model MS250.



    IMG_1328.JPG IMG_1329.JPG

    IMG_1335.JPG IMG_1338.JPG

    Next is a pic of a late model muffler next to a muffler that was on an early model 023. You think these saws got choked down any over the years?

    IMG_1444.JPG
     
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  2. MasterMech

    MasterMech The Mechanical Moderator

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    Proceed with caution, this will make your little saw quite loud.

    I cut the roof of the baffle out. Remove the entire perforated area.

    IMG_1319.JPG

    Next, remove the entire area that is recessed under the deflector.

    IMG_1323.JPG

    Open up the deflector a bit...

    IMG_1325.JPG

    Sock deflector opening vs modified. I have ground on the openings some to open them up further but honestly, I think the gain is minimal and the saws run just as good if you just pry 'em open some.

    IMG_1326.JPG IMG_1324.JPG

    You can either re-install or toss the screen, I like to keep 'em in. Now time to re-tune and go cut some wood!

    NOTE: If you want a bit more power but don't want to make a whole lotta noise, leave the internal baffle alone. Your saw will get a bit louder but not nearly as much as it would if you go all the way.

    Lousy pic but here it is on the saw.

    IMG_1456[1].JPG

    It should run pretty good when you're done. ;)

     
  3. w8ye

    w8ye

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    I have three of these saws and all are 025 or MS250 and I also have a extra engine unit.
    The original muffler on the 025 was two piece, held together with the mounting bolts.
    You still see these on Ebay. But the Chinese replacements are mostly crimped together.
    The come apart mufflers are easy to open up the cage for it comes out as its own little device.
    With the crimped mufflers you have to reach through the back opening to open up the cage.
    Opening up the muffler makes these saws really come alive but they are loud. In a buried bar
    situation in pine, they will make the bark glow red.
     
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  4. Gasifier

    Gasifier

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    I have talked with some guys about modifying a saw. Does or will it reduce it's trade in value? In the event you may trade it in for a newer/larger saw, etc. Can it create any problems with performance and reliability of the saw in the long run?
     
  5. clemsonfor

    clemsonfor

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    Maybe trade value if you pointed it out gas. But should allow the saw to run better and extend life.

    But you shouldnt really trade a saw to a dealer they won't give you anything as they have to resell it. There going to steal it.

    Sell it here in the classifieds or on CL. But here you will get good money and its easy to do.
     
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  6. MasterMech

    MasterMech The Mechanical Moderator

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    It's a very fickle thing. It depends very much so on who did the work and what was done. And of course who is looking to buy.

    Here within the chainsaw enthusiast community, a MasterMind Worksaws, Wicked Worksaws, or similarly recognized sticker adds to the value of a saw considerably. Some guy who saw your add on Craigslist may not give two chits as long as the saw runs. I also would not expect an average dealer to offer you more for a modified saw. A simple, and neat muffler mod that is reasonably "stock appearing" should not reduce the value of the saw to any customer really. If it has a gaping hole for an outlet or 4 pipes sticking out of it, it might be an issue.

    The same applies to modifications and their effect on the saw's reliability. Certain builders build with longevity in mind. Others may build for power, and most I'm sure would build to order if you desire.

    I have two saw's built by Randy (MasterMind) and I know I'm not worried about wearing out either one of them. ;)
     
  7. Cut4fun

    Cut4fun

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    Just make sure you put a fully adjustable carb with H side on them to retune carb after modding mufflers. Otherwise they will be leaner then they were and fry themselves if to lean.
     
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  8. MasterMech

    MasterMech The Mechanical Moderator

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    I haven't seen one of those fixed jet carbs in quite awhile actually.

    He's right folks, muffler mods are not for non-adjustable carbs.
     
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  9. Cut4fun

    Cut4fun

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    w8ye wasnt the carbs like $23 brand new at dealers.

    I know the ones I have had in, some of the carbs wasnt adjustable. The ones that went back to costumers didnt get muffler modded without a a new carb with H side. If no carb no MM.

    w8ye did carb swaps after getting saws from me needing H sides.
     
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  10. SquareFile

    SquareFile

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    If anyone mods there muffler they should clean the inside thoroughly by any means necessary. I'm sure the OP did.

    You don't want shavings getting back into the power head.

    Also, spend a few extra minutes to blend rough edges, burrs, and serrations that in time could release or rust off in time and causing damage.

    44623-d4becfba304d50e7c4b75cd82a14644a[1].jpg
     
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  11. MasterMech

    MasterMech The Mechanical Moderator

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    SquareFile is right and I did clean up the baffle opening some in that one. I wish I had a pic of that or one I just did for Ray but you guys get the idea of what needs to be done.

    Before the muffler goes back on the saw, it gets a soak in my parts washer and a thorough blow out. If it's got lots of sticky goo inside, I'll heat it up to bake it off and make it less susceptible to retaining shavings.
     
  12. raybonz

    raybonz Moderator

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    Brian I can take a pic and post it if you want?
     
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  13. raybonz

    raybonz Moderator

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    Just took a walk down cellar and here is a pic of the muffler..
     

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  14. HoneyFuzz

    HoneyFuzz

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    I have had a few of this family of saw ! Great saw.... And with the muffler mod as shown..... They respond very well ! They do become louder.... And as stated above.... Be careful on the 170/180 and others with the non adjustable carbs. The muffler mod tends to lean out the mixture. And theres no way to adjust them.... Unless you switch to the fully adjustable carb for an 025. I personally love these saws !
    I did a muffler mod on a 180 i had. Talk about a screamer !!! Lol. Had to buy a new muffler so i didnt fry the thing !
     
  15. raybonz

    raybonz Moderator

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    FYI my 023 has a fully adjustable carb..
     
  16. HoneyFuzz

    HoneyFuzz

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    I think the 021,023,025 had the adjustable carb. But i could be wrong.
     
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  17. MasterMech

    MasterMech The Mechanical Moderator

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    Would you believe that I've never modded the muffler on a 170/180? Lol. My buddies 018 was in here recently but I think it got away unscathed.
     
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  18. HoneyFuzz

    HoneyFuzz

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    Lol ! Its fun. They screeeaaammm like a banshee lol !!
     
  19. clemsonfor

    clemsonfor

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    I parted out an 025 this last year. And it had a fully adjustable carb with H and L needles.
     
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  20. nsmaple

    nsmaple

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    I've got a stock 250 - this looks interesting.

    Have you ever encountered a 250 that sometimes refuses to start when shut down warm/hot? Mine does that once in a while - quite frustrating. Often wondered if it got some kind of vaporlock thing going on...