Lakeside53's --361 muffler mod w/photos

[stihl 440]

Dp

Just modded my 280's muffler tonight. I used two 1/2" copper pipe, brazed them in, and took the baffle out, and cut the deflector off and blocked off the stock outlet. I put her all back together and started her up and adjusted the idle first, the tached it it was at 14,100. I turned it back down to 13,500 which is where it was before the mod. It is a walker style mod. It cuts and sounds awesome!:greenchainsaw:

 

[country boy]

For those of you that have done the mods on the 359's, what size holes are you finding works the best?

I am not real sure what works the best but on mine i went with dual 1/2" id pipe and crimped off the pipe going to the factory top exaust outlet afraid of exceeding the 85% rule. <a href="http://s220.photobucket.com/albums/dd71/timberguy/?action=view&current=2chainsaw004.jpg" target="_blank"><img src="http://i220.photobucket.com/albums/dd71/timberguy/2chainsaw004.jpg" border="0" alt="Photobucket"></a>

 

[user 19670]

Josh, I understand what you are saying, but you can buy stainless steel cheaper in a scrap yard than you can buy black pipe in the hardware store. You can buy stainless at $1.00 a pound. Sure you can buy the cheap steel there too at .10 cents a pound, but why not use stainless?

Theres no such thing as a new diamond.

By this I mean that two dollars will buy you enough material to build the highest quality stainless steel piped muffler. Stainless steel will never deteriorate, just like diamonds.

Yes, you can shop at Mc master to buy all new materials...(thats crazy!)
but even if you pay $2.00 a pound in a scrap yard you will have enough material to do all your saws.

And stainless steel is steel. Although I have not tried to braize it, I would see no reason you couldnt do it. If you know anyone with a welder, you know someone who can weld the pipe in. Its not magic. Use the smallest wire avail. and keep the hole tight and clean. Go slow on the thinner pipe. Use thicker walled pipe if you can get it. On the thicker walled stuff, weld on the pipe, and move the weld puddle into the muffler material with quick motions and stop. Let it cool and repeat. Its very easy to burn through the muffler and make big holes. Its also very easy to avoid doing that.

I live in an area with huge medical research facilitys, food preparation plants, and NASA. We even have a place that is building parts for secret satellite laser weaponry. There is never any shortage of stainless steel tubing.

Do not be afraid of using stainless, its just steel with a little nickle added. And if you really can not find the material to build a nice one, shoot me a pm.

Originally stainless was steel and some nickle but actually, there are now more stainless alloys than you can imagine.

Stainless doesn't always mean non-rusting (try Wally World stainless cutlery and see what I mean).

Stainless steel is really a misnomer in some cases. Many alloys exist that have no steel at all in them.

Some stainless doesn't braze well (or easily for that matter) and it takes better than a bottom of the line MIG from the local hardware store to manage welding stainless properly (and a different gas than you use with ferrus metals). Special alloy electrodes (wire) are required to join ferrus metal to stainless with any degree of reliability under any conditions and then we add heat/cool cycles.

 

[Tzed250]

Gordie, all steel is ferrous. <[sp] Stainless implies a minimum nickel content.

 

[sawfix]

Gordie, all steel is ferrous. <[sp] Stainless implies a minimum nickel content.

i think ya got that backwords stainless has a high chromium or nickle content like inconel.

 

[slabhead]

I pulled the screen on my 365 Special, totally gutted the insides.Is there any thing else to be gained over expanding the factory outlet? easily done w/ big blade screwdriver.Noise is not a problem-can't hear anyting w / muffs on,

 

[Bowtie]

From all the reading and watching others, i believe I am gonna do mine.i love the way the saw cuts now. Can't wait to see it after the mod. All i need is the pipe and i'm gonna check on some on monday. Did anyone else notice a huge difference in their 361 after about 10 tanks of fuel or so.Mine is nite and day in power. Be the way awsome work lakeside joe

Do the muffler mod like Lakeside53 did and you will be very impressed. I did that and switched from a 7 tooth rim sprocket to an 8 tooth rim, and Its an awesome machine! (With sharp Stihl RSC chain)

 

[Greg Lees]

I have everything to mod my 361's muffler, but I'm having trouble finding the right diameter pipe (.625-.630 OD). All "1/2 inch" conduit is really 5/8" ID and is too large for the 16mm screen to fit over. Has anyone found a supplier that has the proper size?

 

[Bowtie]

I have everything to mod my 361's muffler, but I'm having trouble finding the right diameter pipe (.625-.630 OD). All "1/2 inch" conduit is really 5/8" ID and is too large for the 16mm screen to fit over. Has anyone found a supplier that has the proper size?

True Value Hardwae

 

[djauto]

I have everything to mod my 361's muffler, but I'm having trouble finding the right diameter pipe (.625-.630 OD). All "1/2 inch" conduit is really 5/8" ID and is too large for the 16mm screen to fit over. Has anyone found a supplier that has the proper size?

Greg,

I used a 1/2" BOLT SPACER, like bowtie said, any hardware store should have it. The 16mm screen fits perfect in it. It is rolled steel so it has a seem along it that you can easily weld or braze up. The ID could be a little larger with thinner wall thickness for better flow (they come with .060 or so wall thickness and 5/8 or .625" OD with .505" ID) but it works excellent and cost $.18.

Brian

 

[Bowtie]

Greg,

I used a 1/2" BOLT SPACER, like bowtie said, any hardware store should have it. The 16mm screen fits perfect in it. It is rolled steel so it has a seem along it that you can easily weld or braze up. The ID could be a little larger with thinner wall thickness for better flow (they come with .060 or so wall thickness and 5/8 or .625" OD with .505" ID) but it works excellent and cost $.18.

Brian

Good point on the ID of the bolt spacer pipe. I dremel all my modded 361 mufflers until they make me smile.

 

[Wet1]

Can anyone advise me on how to retune after a muffler is modded, I ve setup carbs before, only on stock saws though. I usually hear people just say a little richer. Kinda hard to go by that. I want to do my Husky 394xp.

Any other tips for tuning after this mod???




I'm considering doing this on my 036, is there much of an improvement on this model?

 

[woodchuck361]

I'm going to try something new. First off anyone found a source for spark arrestor screen? I have opened my 361 muffler and cut the small outlet port completely out all the way down to the spark arrestor. Enlarged the exit hole and will make a spark arrestor "sock to fit over the metal pipe with all the holes in it. Not sure of the proper name of it.
http://www.arboristsite.com/attachment.php?attachmentid=74184&d=1215652585
muff 1.jpg
http://www.arboristsite.com/attachment.php?attachmentid=74185&d=1215652618
muff2.jpg

 

[Lakeside53]

How will you ever clean it?

 

[woodchuck361]

Well...... how often do they need cleaning? Its either that or no spark arrestor at all. I don't cut on government land or anywhere that requires one. just though it would be a good idea, and if the arrestor were really large it would not need cleaning that often.

 

[Lakeside53]

Maybe so.. but that why all spark screens are accessible...

I clean (burn off with propane) about 5 a week... mainly due to dumb operators, but...

 

[woodchuck361]

after the muffler mod the high side should be turned out about 1/8-1/4 turn? mine was all the way on the on the limiter stop. I pulled both limiter caps, trimmed the stops off and reinstalled in the same location the screw will now turn more but how much? I have gone about 1/4 turn to the left should I be going to the right? Do the screws on all saws adjust richer to the left and lean to the right or do I have it backwards? I have only started it saw up and blipped the throttle twice not sure on the adjustments. Its to expensive to screw up. thanks

 

[Lakeside53]

You have it correct.... start it and tune it...

 

[woodchuck361]

YOU TRULY ARE THE MAN THANKS AGAIN. Oh I am going to source another muffler and make a pipe that goes from the enlarged exhaust port to the stock spark arrestor location and make a press fit connection like the stock muffler. I will cut out the spot welds that hold the arrestor assembly in place, trim the small pipe and braise a larger pipe in place. Then fit and braise a connector sleeve in the exhaust opening. Then tac the assembly back in place. The same system as stock Just with a larger pipe . Your words about the arrestor needing to be serviceable are TRUTH. After thinking about it long and hard I can't think of another or better way to do it while keeping the stock look, and I do think the arrestor is important. I will try to post up pics as the process progresses. Now to find a muffler Thanks again Lake.

 

[Greg Lees]

Well, after looking in every hardware and plumbing store in Nashville/Franklin for the right kind of tubing for the muffler port, I went to a machine shop. The owner didn't have anything on hand, but he did have a catalog from McMaster-Carr...

Here's the website address:

http://www.mcmaster.com/

...and here's the part number for .625 OD, .350 ID steel tubing:

89955K27

The tube is a perfect fit both inside and out. The screen fits, the clip fits. Only downside is you have to buy 6' length. It's $23 for the tube, plus shipping. You'll have enough tubing to mod saw mufflers for a while....

Greg