Muffler Fun (Husqvarna 55)

[ChillyB]

New-to-me 55 is too nice to leave stock after detail cleaning and piston inspection. Getting 150 psi, haven't pressure tested crankcase yet, but I am determined to not melt any more of the clutch cover. So pulled the muffler for a good cleaning and some amateur modding.

First step is to de-rust. I am a YUGE fan of Evapo-Rust. Non-toxic, pH neutral, won't harm base metal but somehow kicks rust's butt. It isnt cheap so poured container half full and laid a shop towel on top to keep exposed area wet by wicking. Otherwise I need to use twice as much for full immersion (and because this is all I had left in my jug).

 

[ChillyB]

After a day of soaking and some wire brushing to remove the sludge. As the rust is dissolved a slimy black layer is left on the metal. Maybe it’s residual carbon as the iron oxide goes into solution? I don’t know. It eats rust and not the base metal. That’s what I care about. Can leave metal in the stuff for a week. It won’t hurt it.

 

[ChillyB]

Back in the tub. While it doesn’t seem to dissolve carbon (at all) it does soften it and I’ve had large flakes of it come off from inside the can.

 

[ChillyB]

I’m thinking to grind off the welds for the side discharge, blank it off, hog out a hole somewhere, weld in a stubby pipe not directed at any plastic.

Once the rust was gone the two halves pulled apart easily. Note the slimy carbon layer starting to peel away. Maybe Evapo-Rust is useful to decarb mufflers, pistons, cylinders?

 

[ChillyB]

Excised the discharge hood scoop, was abusing my Dremel to grind off the perimeter but will switch to my die grinder tomorrow. Then I'll patch these holes shut.

 

[ChillyB]

Check out these tubes. Theae are the tubes from a Poulan catalytic converter muffler which surround the mounting screws. I think a set of true duals should be worth what, 10hp?

 

[BrettS]

I’m thinking to grind off the welds for the side discharge, blank it off, hog out a hole somewhere, weld in a stubby pipe not directed at any plastic.

Once the rust was gone the two halves pulled apart easily. Note the slimy carbon layer starting to peel away. Maybe Evapo-Rust is useful to decarb mufflers, pistons, cylinders?
View attachment 987021View attachment 987022

I didn't think to use Evapo-Rust on the muffler, I used good old elbow grease on my 026 muffler, maybe I should have used Evapo-Rust instead looking at those results.

 

[ChillyB]

Next step is to get real clever and use MAPP torch to unbraze the residual metal so you don’t have to grind it away.

Then you order another Chineeee muffler to replace the OEM that you just ruined.

I used the ruined muffler as a donor to patch the new muffler side exhaust after cutting away the “hood scoop”.

 

[ChillyB]

The flared ends of the tubes are inside, giving me a nice joint on which to weld. The Chineee muffler doesn’t come apart so was lucky the tubes fit in the back after a bit of filing to the flares. The halves are brazed together. Not a bad job, either.

 

[ChillyB]

Franken-welds complete. I don’t always suck, but when I do I’m welding in flip-flops. And usually smell a little like beer and bourbon.

 

[ChillyB]

 

[ChillyB]

No more melting the clutch cover.

 

[BrettS]

Franken-welds complete. I don’t always suck, but when I do I’m welding in flip-flops. And usually smell a little like beer and bourbon.
View attachment 987995

I learn't not to mix my drinks, don't ask me how I know LOL

 

[ChillyB]

Curing the VHT. I smell a little like beer and bourbon and not about to put it in the kitchen oven. That’s why a man needs a shed. Am I right, my brothers?

 

[ChillyB]

I learn't not to mix my drinks, don't ask me how I know LOL

Shucks, Pa. It’s a Boilermaker I stir in my belly.

 

[BrettS]

Curing the VHT. I smell a little like beer and bourbon and not about to put it in the kitchen oven. That’s why a man needs a shed. Am I right, my brothers?
View attachment 987998

I haven't seen one of those in years.

 

[ChillyB]

I haven't seen one of those in years.

I know. It’s cool as heck, too. I have a couple round ones for emergencies but I like having it against the wall. I think I paid $40 for it used in the fall? Pretty clean unit. Have a new wick to put in it someday.

 

[BrettS]

I know. It’s cool as heck, too. I have a couple round ones for emergencies but I like having it against the wall. I think I paid $40 for it used in the fall? Pretty clean unit. Have a new wick to put in it someday.

I used to use one, smelled a bit. Don't know what I did with it.

 

[ChillyB]

If you live in middle TN I may have just bought it from your wife. Don’t be too hard on her for selling your awesome heater. She seemed like a nice lady.

There is some additive that knocks the stink back a bit. Also, keeping it running hot and not running it empty helps. Startup and shutdown is where I get most of the smell.

 

[BrettS]

If you live in middle TN I may have just bought it from your wife. Don’t be too hard on her for selling your awesome heater. She seemed like a nice lady.

There is some additive that knocks the stink back a bit. Also, keeping it running hot and not running it empty helps. Startup and shutdown is where I get most of the smell.

Got quite a big ditch to swim between me and the US and I have no wife