Stihl 075AV Muffler repair

[mojo jojo]

Hello, I got nice Stihl 075av but need to repair muffler. There is some big piece broken inside and it is rattling around. Feels big and heavy. Need to take it out, but I am not sure the size and shape is the broken piece. I would like to cut the muffler at the right place and just big enough to take broken part out. So minimum cuting, posibly at the back so I preserve its original look.

Did anyone opened 075 muffler? Any pictures? I would like to see how is built inside before I start cutting.

My looks like that:

[doc henderson]

If you remove the screw does the vented grate come off, and can you look in it that way?
can you shine a light and peak in the grate?
does the screw hold the rattly part, and it is loose?

[mojo jojo]

no,
no,
no.
Screw is there to hold a mesh screen. Those grids are welded on. There is a "tunnel" baffle underneath so you cant see anything inside. Intake is curved 90 degrees, so nothing to see there either.

[doc henderson]

It does not show well in your photos but looks like there is a seam, and I would cut along there and or see if it will pry open.  you can weld it back together.

[mojo jojo]

That seam overlaps and is heavily brass welded. Plus, there is another weld that goes thru the muffler. Too much cutting, grinding and welding.

[beenthere]

What does the loose part bother? Performance? 

[doc henderson]

so live with it or buy a new one...

[mojo jojo]

Not available as a spare part (OEM or AM).
That loose piece inside the muffler can loose carbon built up inside muffler and suck them back in the engine. It can cause damage to piston and jug.

[doc henderson]

saw them new on ebay.

[beenthere]

mojo
Let us know how you plan to do this. And post some pics of the job. Curious too what is rattling around.

Maybe if you get a plasma cutter, you can make a delicate cut and remove or secure the loose piece, then a smooth weld so it looks like factory again.



Also, maybe you would let us know a bit more about your endeavors. And your location in your profile will help us become acquainted too.

[mojo jojo]

And your location in your profile will help us become acquainted too.

I am from the country where your former and future first lady was born.

The saw is actually collectors item. It will run only one or two times a year. So if I will not be sure where and how to cut it open, I will leave it as it is. These mufflers are really scarce and dont want to ruin it.

[sawguy21]

The baffle has come loose. Cut the housing open to access it  then weld a patch over the hole and wear good hearing protectors.

[doc henderson]

maybe you can drill a hole to look in and see, and then spot weld the hole and poss. reattach the baffle in the process.