Lakeside53's --361 muffler mod w/photos

[02powerstroke]

Here's a pic of my MS341 muffler mod.
Simple but effective, only tool i used was a dremel with a 5mm high speed burr then finnished off with a not so aggresive diamond to de-burr the inside, then flushed with brake cleaner and comp air before fitting back on the saw. Outlet holes are only about 1/4" dia, could go bigger if needed but i'm well happy with the result, i can tell the difference in the cut.

whats that just taking the caps off?

 

[constantine]

Anyone on here mod a MS 361? I'm looking to do this to mine.

thanks

Here you go. Check on the "Lakeside53" sticky to see how to do it. It really works. Mod the saw, tune the carb, run about 8-10 tanks through and it's primo!

"MS 361 Lakeside-style muffler mod"

 

[Junkrunner]

Here's one, I did on my 036

 

[rayvil01]

Oxy-Mapp Brazing?

There were a number of posts about using Mapp gas to braze a mod onto the muffler. Sounds like some folks had success and some didn't. Yesterday I was in the hardware store and saw an Oxy-Mapp torch. Seems like that would be a good bit hotter burning than straight Mapp gas.

Has anyone been using one of those for brazing muffler mods?

 

[mustangwagz]

There were a number of posts about using Mapp gas to braze a mod onto the muffler. Sounds like some folks had success and some didn't. Yesterday I was in the hardware store and saw an Oxy-Mapp torch. Seems like that would be a good bit hotter burning than straight Mapp gas.

Has anyone been using one of those for brazing muffler mods?

I've never used the brazing rods myself, i just used my mig. turned the amperage way down and just pretty much stitched it. (Stitching is what i consider several spot welds overlapping each other.) I had no problem with mine yet and i used the heck outta it yesterday.

 

[constantine]

Oxy-MAPP Brazing

There were a number of posts about using Mapp gas to braze a mod onto the muffler. Sounds like some folks had success and some didn't. Yesterday I was in the hardware store and saw an Oxy-Mapp torch. Seems like that would be a good bit hotter burning than straight Mapp gas.

Has anyone been using one of those for brazing muffler mods?

That is exactly what I use. If you burn straight MAPP gas, the temperature is really marginal for brazing. MAPP alone won't even melt a nickel-silver rod. Using the oxy-MAPP gives a higher temperature. The brass melts quickly and flows into all the crevices like it should. For $55 you can't beat the small oxy-MAPP setup. For ordinary soldering of copper pipe and the like, you just don't use the oxygen tank.

I've found that one of the factors in successful brazing is to use a low velocity flame. That way, the brazing liquid doesn't get blown around, and can seep in and fill all the spaces between the parts. Even when using oxygen, you have to heat the parts thoroughly before you touch the rod to the work. It should melt right away and the melt should flow freely, like water.

 

[rayvil01]

That is exactly what I use. If you burn straight MAPP gas, the temperature is really marginal for brazing. MAPP alone won't even melt a nickel-silver rod. Using the oxy-MAPP gives a higher temperature. The brass melts quickly and flows into all the crevices like it should. For $55 you can't beat the small oxy-MAPP setup. For ordinary soldering of copper pipe and the like, you just don't use the oxygen tank.

I've found that one of the factors in successful brazing is to use a low velocity flame. That way, the brazing liquid doesn't get blown around, and can seep in and fill all the spaces between the parts. Even when using oxygen, you have to heat the parts thoroughly before you touch the rod to the work. It should melt right away and the melt should flow freely, like water.

Many thanks to you for the info. MIG is somewhere in the future. But, this Oxy-Mapp is something I can do right now.

 

[ktmsooner]

No, he didn't just take the caps off, look close and you will see the small holes that he made with a dremel tool.

 

[Diesel Pro]

Here's my 345 muffler mod. I slit the deflector on the sides and folded it back to minimize the welding. I have a Miller 250X and had a bit of trial and error geting it turned down low enough with the .030? wire.

 

[Junkrunner]

Here's my 365 with its "brazed" pipe.

 

[o8f150]

i bought a poulan tiger shark the other day just to use as a debranching saw,,,i only gave 50 for it,,,runs great for a used one,,so i figured i would try a muffler mod on it,,had nothing to loose,,,,the exit ports on this one is on the backside of the muffler,,,,when i pulled it apart the screen was on the entrance of the muffler,,,,so all i had to do was drill a 1/2 inch hole on the front side of the muffler and deburr it,,fired it up and the only adjustment i made was turning the idle down a tad,,,seems to run a little bit better,,not much louder either,,i wasn't expecting to much out of a 33 cc saw,,,ohhhh yea,,,for a used saw,,the piston looked dang near new,,you had to look real close to see the 1 small scuff mark,,,,guess i didn't go to wrong

 

[halfskip]

how about ms362 mufflers?

Would a ms362 muffler mod be the same as a ms361. I was thinking about the lakeside style muffler mod.

 

[halfskip]

ms362 exhause port

Also wondering if anyone has calculated the exhaust port area on a ms362 at the piston.

 

[teatersroad]

346xp cat muffler mod.

Knew little of muffler mods before joining this group, so thanks.

The photos should explain the method pretty well. Removed muffler, and from the cylinder side drilled out existing 1/8" holes to 5/16", 9 holes total, plus existing 1/8 holes I could not reach. The black tube you see flows from hollow chamber downstream of catalitic plate and out the exhaust. Could probably be cut to allow flow from the upstream side.

For the additional port, I drilled a hole and tapped it to 3/8" mpt. At first I finished it off with a black pipe 3/8 to 1/4 bushing I had drilled out a little. Temporary as I tried to figure how I was going to get a spark screen in there.

That solution. 3/8" mp to 1/2" compression. I set the fitting; btw take care when drilling and tapping such thin walled stack. I'm impressed and comfortable with how much purchase I have with those threads.

Ground down the shoulder (?) of the compression nut so it would seat more fully. Set a #40 stainless aerator screen over fitting and locked into place with the compression nut.

Total cost. Fitting $3.49, Screen 35 cents. I'm pretty happy with it. Not a lot of cool factor, but finished and servicable. As a coincidence my Husky scrench fits the compression nut.

Saw is modded in other fashions as well, but I'll share that in a thread when it's done.

Regards.

 

[constantine]

NPT reducers

I like your use of the NPT reducers, 'cause I use them myself. Do you plan to solder that brass fitting in place? I'm thinking that it may vibrate loose when cutting. The way you handled the screen is very neat.

 

[teatersroad]

I like your use of the NPT reducers, 'cause I use them myself. Do you plan to solder that brass fitting in place? I'm thinking that it may vibrate loose when cutting. The way you handled the screen is very neat.

thnx,

seems like solder would be a good idea, wonder if I could sweat it in ??. The fitting takes up nicely, and have had it out a few times in my building it. solder or locktite at some point.

I haven't found again the usfs mesh req. for spark screen. hdwr. store had a variety. I cut on private mostly anyway, but a spark areester is wise at times.

I saw another npt used here at one point, maybe that was yours.

regards

 

[matt9923]

I wouldn't permanently attach it, you want to be able to clean the screen, that's one of the best parts of that mod.

 

[teatersroad]

I wouldn't permanently attach it, you want to be able to clean the screen, that's one of the best parts of that mod.

Right, Its the fitting to muffler that gets soldered. Not the compression nut to fitting that holds the screen in place.

 

[matt9923]

Right, Its the fitting to muffler that gets soldered. Not the compression nut to fitting that holds the screen in place.

ohh, makes seance. misunderstood ya

 

[teatersroad]

A person could use 1/2" mpt to 5/8" compression if they wanted a bigger opening. Aerator fits better there too, though trimming's no big woop.