359 Muffler Mod

[Jmaffei]

Hello,
I realize there are a ton of muffler mod posts, and some with the 359, I am just trying to get a quick consensus before I do it. I have bought the deflector and screen for the 288 from baileys and that is the route I would like to take as I have no welding skills or equipment. What size hole would be a semi-conservative hole to drill? Also, should I drill that same hole through the middle baffle in case it is a limiting factor? Does anyone know roughly how much power this is going to give me? Also, I have a tach, do I just keep it tuned to 13 to 13.5 k like it has been? Thanks, James

 

[Diesel Pro]

I did mine with the holes ground into the tubes using the bolt tubes as the additional outlets. Very simple and no welding. I did add a hole through the center baffle.

 

[sbhooper]

Here is what I just did to mine.

I drilled a hole that is about 5/8 or so (not measured, but smaller than what the deflector will cover). I drilled two 3/8-inch holes through the center baffle toward the side with the new hole.

I attached the deflector/screen centered over the hole with a couple of metal screws. I then took a small ball peen hammer and tapped the edges of the deflector down to the contour of the muffler. It worked perfectly.

I tuned the saw to around 13,500 as that is listed as suggested max. I tend to stay on the conservative side of the rpms.

I have not put it in wood yet due to weather, but hopefully tomorrow it will see a live ash and large cedar tree.

I can't say what the percentage increase is, but it runs great and sounds great.

 

[Diesel Pro]

Will those sheet metal screws actually stay tight? I would guess with the heat and vibration they won't as the threads are so coarse.

 

[pioneerguy600]

Will those sheet metal screws actually stay tight? I would guess with the heat and vibration they won't as the threads are so coarse.

Its about the best you can do if you dont weld. I do weld all of mine as the screws have always worked loose on ones I have seen done.
Pioneerguy600

 

[Diesel Pro]

Pop rivet with a backing washer.

 

[Jmaffei]

Hey guys,
Thanks for the responses. sbhooper, can you remember what kind of adjustments you made to the carb? I would guess richen it up a bit. Will those screws be okay if you just make sure they are periodically tight or are they going to eventually strip out?

 

[Jmaffei]

Also, Diesel Pro, what size holes did you put in the bolt holes and how many? That actually seems like a really smart idea. Thanks.

 

[sbhooper]

Time will tell, but I just put some super glue on the screws before I put them in. If you make it permanent, you cannot take the screen out if for some reason it gets carboned up or something. A touch of epoxy or anything like that should help keep them from falling out. If it gets too bad, I guess I will have to go get me an oxy/mapp and braze them in.

I did not really keep track of what I did to the carb screws. They are probably a little richer, but I just watched the tach and adjusted accordingly. The tach will tell you which way to go.

 

[JohnS]

Silver solder

I have had great luck using silver solder on mufflers. It comes out extremely neat. You could have that deflector looking like the muffler came that way. No screws even to medd with.

Just clean it up and flux it where you want the solder to flow/go. If you know anyone that can teach you a little about using a torch you will find a million little thngs to do with it. I fixed a chain tensioner that snapped in about 20 minutes that would have cost me days and $20 - been fine for a year now. People are often fascinated with TIG and it is awesome from what I can see, but a torch is much more forgiving, workable, versitale and simple. Brazing in the right situation can be quite strong too.

Try it and I promise you'll be glad you did. You can get carry pack of Oxy and Acetylene with torches for not much at all. You'll pay for it as soon as you even start to see what it can do.

Anyone agree

 

[Diesel Pro]

Also, Diesel Pro, what size holes did you put in the bolt holes and how many? That actually seems like a really smart idea. Thanks.

Check out the last couple of pages in the DIY muffler mod thread. I forget who the OP was, but he had some nice pics showing the slots.

 

[sbhooper]

The weather finally got better and I exercisede the saws a little today. The 359 and the 361 got some time in the wood. I cut down an 18-inch live ash and 22-inch live cedar and cut them into firewood. Both saws performed great with the muffler mods and no screws fell out-yet!

 

[nmurph]

when i got my 262 project, the muffler did not have a baffle. i used the 288 baffle and sheet metal screws. it has at least 100 hrs on the screws and they have not fallen out.

 

[mirkaba]

I have had great luck using silver solder on mufflers. It comes out extremely neat. You could have that deflector looking like the muffler came that way. No screws even to medd with.
Just clean it up and flux it where you want the solder to flow/go. If you know anyone that can teach you a little about using a torch you will find a million little thngs to do with it. I fixed a chain tensioner that snapped in about 20 minutes that would have cost me days and $20 - been fine for a year now. People are often fascinated with TIG and it is awesome from what I can see, but a torch is much more forgiving, workable, versitale and simple. Brazing in the right situation can be quite strong too.

Try it and I promise you'll be glad you did. You can get carry pack of Oxy and Acetylene with torches for not much at all. You'll pay for it as soon as you even start to see what it can do.
Anyone agree

Howdy.......What temp silver solder do you use? What flux do you use? The solder usually comes in easy, medium and hard. The harder it is the higher the temp. I too have brazed lots of things with silver. Kind of spendy but pretty dang handy. Going to try. a couple of muffler mods. 044 and 046. I do lapidary and make silver jewelry and have a few pretty cool tools including the Smith "Little torch" that can crank out up to a 6000 degree flame. Bob

 

[blsnelling]

Will those sheet metal screws actually stay tight? I would guess with the heat and vibration they won't as the threads are so coarse.

I've never had them back out, and never heard a complaint from a customer.

 

[mirkaba]

I was figuring on brazing on deflectors and screen keepers with a screw to hold the screens in. I have never had screws fall out either. They tend to tighten up with use. Bob