Questions Working on my new 046

[1 stihl nut]

I just picked up an 046 off ebay and decided first thing on my list was to do some muffler modding.

I pulled the front of the muffler off and it was basically empty with no baffles inside, but there was only a port on the bar side and it seemed kind of small so I drilled a 4 3/8" holes on the front side, put it back on and proceeded to tune it. (I'll worry about the screen stuff later if need be.) At the same time, I opened up the muffler on my 029 and retuned it as well, and headed off to test them a little.

The 046 seemed to be running strong, but when I was running it overhead, it was leaking fuel quite profusely. At first I suspected I had a cracked tank. Then I ran the 029, and while just revving it, it was also leaking gas out the bottom. I pulled the back cover off and could see that the gas was coming out of what must be a vent hole that looked like it is supposed to have a rubber hose on it that I would suppose would be hooked to something else. After seeing where the fuel was coming from on this, I looked for the same thing on the 046. The 046 has a white venting mechanism that appeared to be in place, but would allow fuel to exit rather easily.

My 029 has never leaked before, and while I have just acquired the 046, I can't help but to wonder if I've done something to cause this on both of these? It seems highly coincidental that I've just performed similar operations on both of them, and now they both seem to have fuel venting problems.

Anybody have any insight on this? Thanks!

 

[old-cat]

I'm not trying to put you down but that is a very excellent muffler, UNTIL you punch holes in the front! All it needs is to open the existing outlet as far as it will go without going forward. Another option is, buy the optional, STIHL front cover with a screened port, called dual port.

 

[Saw Dr.]

It is almost certainly just a coincidence that you have fuel leaks. There is a little red "umbrella" valve under that white thingy on the 046 that is likely rotted out. On the 029, almost every 1127 series saw I see is missing that vent assy. It is just pressed on. You can make one yourself, or pick one up at any decent dealer. Both cheap and easy fixes. Hopefully you removed the muffler cover when you drilled it out, as a damaged top end is not a cheap or easy fix.

 

[Philip Wheelock]

I just picked up an 046 off ebay and decided first thing on my list was to do some muffler modding.

I pulled the front of the muffler off and it was basically empty with no baffles inside, but there was only a port on the bar side and it seemed kind of small so I drilled a 4 3/8" holes on the front side, put it back on and proceeded to tune it...

Not sure drilling holes in the front side is a good idea because a lot of the time the front of the muffler will be tight up against what you're cutting. Better idea is open up the existing side outlet or get the optional dual-port muffler cover.

 

[1 stihl nut]

I'm not trying to put you down but that is a very excellent muffler, UNTIL you punch holes in the front! All it needs is to open the existing outlet as far as it will go without going forward. Another option is, buy the optional, STIHL front cover with a screened port, called dual port.

I thought I had read it was a good muffler, as there aren't baffles and such, it just didn't seem like a lot of exhaust exit area. And I was feeling a little antsy. I plan on looking for a dual port anyways.

It is almost certainly just a coincidence that you have fuel leaks. There is a little red "umbrella" valve under that white thingy on the 046 that is likely rotted out. On the 029, almost every 1127 series saw I see is missing that vent assy. It is just pressed on. You can make one yourself, or pick one up at any decent dealer. Both cheap and easy fixes. Hopefully you removed the muffler cover when you drilled it out, as a damaged top end is not a cheap or easy fix.

Thanks! That was my primary question. Does the white piece remove easily, or should I just have the dealer deal with it? And yes...I removed the cover. My stupidity does have it's limitations.

Not sure drilling holes in the front side is a good idea because a lot of the time the front of the muffler will be tight up against what you're cutting. Better idea is open up the existing side outlet or get the optional dual-port muffler cover.

You are quite right. Thanks for responding. My best learning is done by mistakes....and now at least I know I made a couple.