New EPA/CARB scam to prevent removal of a cat muffler?

[PasoRoblesJimmy]

I'm wondering if the EPA or CARB has come up with a new scheme or scam to block removal, replacement or modification of a cat/non-cat muffler.

The non-cat muffler on my Husky 445 (purchased new Nov 2009) has 2 round metal rings pressed with an interference fit into the 2 deeply recessed holes on the front side of my muffler. The metal rings block access to the hex head muffler bolts located just behind the 2 force fitted rings. The rings look like thin flat washers with the center drilled out. The metal rings have writing on the front surface of them. The metal rings are missing from the IPB for the Husky 445. Will removal of these rings void the warranty?

My Stihl SH86 Blower/Vac (purchased May 2009) also has the same exact force fit rings pressed deep into the front holes of its cat muffler. However, on the Stihl, I can successfully insert a T27 bit into the Torx head muffler bolts thru the center of the ring.

I am trying to figure out how to remove the non-cat muffler on my Husky 445 to see what is lurking inside of it. How do you remove the 2 metal rings blocking removal of the hex head muffler screws with a socket wrench? Can these 2 rings be removed with a drill or a screw extractor? Can these 2 rings be reinstalled after they have been removed? Is there a simple way to remove a muffler without destroying the rings or the muffler?

I'm not interested in a radical racing saw. I just want a working saw that isn't turned into a gutless wonder by the Political Correctness of the EPA or CARB.

I'm confused about the purpose of these retainer rings. Are these pressed-in rings intended to prevent removal of the muffler bolts?; Or, are they just intended to prevent the loss of muffler bolts loosened by vibration?

 

[drkptt]

It's not EPA or CARB mandated; must be to prevent bolt loosening due to vibration or thermal cycling. The higher temperatures of the cat mufflers have made keeping them bolted to the engine more of a challenge.

The EPA allows a manufacturer to specify that cleaning carbon out of the exhaust port is normal maintenance. If it is specified then during the rated life emission test the saw can be shut down and muffler disassembled to do this. Thus the EPA doesn't require tamper-resistant muffler bolts.

 

[Gizzard]

I checked the hex bolts in mufflers on my 450 and 435 Husqvarna last week. They are both 2009 models and 5mm allen/hex wrench fit them fine. No pressed rings over them.

Maybe its a California thing?

 

[RTK]

Maybe its a California thing?

No doubt

 

[logging22]

Gotta be a cali thing mang!

 

[bitzer]

The muffler is as open as can be inside. The 455 is a strato so no cat. Its an empty box and a muffler mod will not do much for this saw because it is a strato if thats what you are getting at. Actually a muff mod will give you faster and faster cuts when you go leaner and leaner. The bell curve fall off for timed cuts is well beyond lean on this saw. So tuning in the cut by timed cuts will not work. I have not heard of rings like that on the muffler bolts.

 

[PasoRoblesJimmy]

I have been too busy to check it out with my local Stihl/Husky dealers. Since these washer-type rings are almost as ridiculous as Kalifornia's Governator, I'm beginning to suspect that it could be something mandated by C.A.R.B.

 

[PasoRoblesJimmy]

It's not EPA or CARB mandated; must be to prevent bolt loosening due to vibration or thermal cycling. The higher temperatures of the cat mufflers have made keeping them bolted to the engine more of a challenge.

The EPA allows a manufacturer to specify that cleaning carbon out of the exhaust port is normal maintenance. If it is specified then during the rated life emission test the saw can be shut down and muffler disassembled to do this. Thus the EPA doesn't require tamper-resistant muffler bolts.

There is no way that these flat washer-type rings can keep a bolt from vibrating loose. They might save a bolt from completely falling out onto the ground and getting lost, but they won't stop a bolt from twisting loose from vibration. These flat washer-type rings almost look like something invented by the Halfwits of Hollywood.

BTW, the Governator of Kalifornia is a halfwit AND he is an actor from Hollywood. In addition, most of the bureaucrats in Sacramento are blithering idiots.

 

[4g63det]

Is that what you are reffering too? I am wondering the same thing...

 

[PasoRoblesJimmy]

Is that what you are reffering too? I am wondering the same thing...

Yup!!!! Them flat rings at the bottom of those front muffler bolt holes are almost impossible to see or photograph. They must be the Wet Dream of an EPA bureaucrat.

 

[indiansprings]

They just pop out with a screw driver, then you can tap them back in with the handle of the screw driver when you get done with the muffler removal/mod.

 

[Zero Gravity]

Those clips are for assembly aid. They prevent the bolt from falling out during assembly.
ZG

 

[4g63det]

Those clips are for assembly aid. They prevent the bolt from falling out during assembly.
ZG

Nice, ill have to pop em out and have a look around inside that big ol muffler...

 

[mtngun]

Actually a muff mod will give you faster and faster cuts when you go leaner and leaner. The bell curve fall off for timed cuts is well beyond lean on this saw. So tuning in the cut by timed cuts will not work. I have not heard of rings like that on the muffler bolts.

Interesting. So.... how do you tune a strato -- is it still best to do it by ear ?

 

[PasoRoblesJimmy]

I checked the hex bolts in mufflers on my 450 and 435 Husqvarna last week. They are both 2009 models and 5mm allen/hex wrench fit them fine. No pressed rings over them.

Maybe its a California thing?

You are absolutely right. I removed both muffler bolts tonight with a 5mm allen/hex wrench. There were no rings pressed over them. My 69yo eyes mistakenly thought that the machined front surface of the bolts included an extra "ring" pressed on top of them.

The inside of the non-cat muffler on my 445 Husky is completely hollow. The main restriction in this muffler is a tiny oval hole (approx. 1/4" in diameter) located below the spark arrester screen. After removing the muffler screen, I spread the deflector to open it up and make it wider. I then inserted the shaft of a Dremel cutter thru the deflector and reamed out the tiny hole underneath the muffler screen to about 1/2 inch in diameter.

It is a good idea to check your rpm with a digital tach before you try to mod the muffler. You will probably need to fatten up the H screw after you mod it. Tuning by ear only (or with timed cuts) will miss the mark.

Brad Snelling offers excellent advice and info on tuning strato charged saws.
NE 346XP - Affects of Cat Muffler & Muffler Mod - Porting & Popup To Come
http://www.arboristsite.com/showthread.php?t=118591

 

[Gizzard]

You are absolutely right. I removed both muffler bolts tonight with a 5mm allen/hex wrench. There were no rings pressed over them. My 69yo eyes mistakenly thought that the machined front surface of the bolts included an extra "ring" pressed on top of them.

The inside of the non-cat muffler on my 445 Husky is completely hollow. The main restriction in this muffler is a tiny oval hole (approx. 1/4" in diameter) located below the spark arrester screen. After removing the muffler screen, I spread the deflector to open it up and make it wider. I then inserted the shaft of a Dremel cutter thru the deflector and reamed out the tiny hole underneath the muffler screen to about 1/2 inch in diameter.

Good deal. Good luck with your 445 mods. Those muffler holes are long and dark to look down into. I keep a small flexible fiber optic light to look at tight places like that on saws and guns.

 

[PasoRoblesJimmy]

Good deal. Good luck with your 445 mods. Those muffler holes are long and dark to look down into. I keep a small flexible fiber optic light to look at tight places like that on saws and guns.

The bolts for the muffler on my Husky 445 have an unusual appearance. The muffler bolts are dull black with their front surfaces machined to a shiny finish. The shiny front surface on these muffler bolts gives an optical illusion that there might be a shiny flat ring pressed onto the top of each dull black muffler bolt.

I really like my new Husky 445. It exhibits quite a bit of power for a small 46cc saw. I checked it with a tach. Out of the box with a mild muffler mod, it was turning 14,290 rpm. I richened the H screw so my Husky 445 is now turning about 12,700 rpm.

Adjustment tool p/n 530035560 is needed for tuning the splined L and H screws on the carb.

 

[bitzer]

Interesting. So.... how do you tune a strato -- is it still best to do it by ear ?

By ear. The 455 I have has a very distinct four stroking sound. I have been told by Brad and experience that tachs are merely for reference once the saw is modded. You can really only tune by ear.

 

[bitzer]

http://www.arboristsite.com/showthread.php?t=118591[/url]

It is a good idea to tach it before and after and it will need richening up. I thought the 445 had a limited coil though. I could be wrong. The 346 is not a strato also. I think in a modded saw all you have is tuning by ear, especially a strato. 12.7k is a safe number to be at either way though.

 

[PasoRoblesJimmy]

It is a good idea to tach it before and after and it will need richening up. I thought the 445 had a limited coil though. I could be wrong. The 346 is not a strato also. I think in a modded saw all you have is tuning by ear, especially a strato. 12.7k is a safe number to be at either way though.

The Husky 445 has a black coil. The Husky 445e with cat muffler could be a different animal. I believe that X-Torq is Husqvarna's nomenclature for strato.