Rattle sound in LS3 engine muffler

[pawter1970]

So my LS3 muffler has a rattle sound in my 2010 Wakesetter VLX, brought it to the shop this weekend and the mechanic told me something is lose inside which causes the rattle but it's not affecting performance, I did read a tread on here regarding muffler issues with LS3's in the past and wondering if there is another fix other than replacing the entire unit.

 

Thank you. 

[Woodski]

@pawter1970:  Sounds like an internal baffle came loose, you can cut the muffler apart and repair the baffle, then simply re-glass the unit back together. PM Michigan Boarder or find his engine thread, he put some pictures on this site as he modified his muffler for larger diameter hoses.  Easy DIY project & saves lots of cash.

@Michigan boarder:  feel free to chime in as one of the forums muffler experts  

[pawter1970]

12 hours ago, Woodski said:

@pawter1970:  Sounds like an internal baffle came loose, you can cut the muffler apart and repair the baffle, then simply re-glass the unit back together. PM Michigan Boarder or find his engine thread, he put some pictures on this site as he modified his muffler for larger diameter hoses.  Easy DIY project & saves lots of cash.

@Michigan boarder:  feel free to chime in as one of the forums muffler experts  

Ok, thank you Woodski, I'll certainly look into this.

[Michigan boarder]

Yo!

My '94 silencer looked like this.  I was changing the engine and wanted larger openings, STE's, etc. so I cut into it. 

The way it works is the exhaust flowed in thru the short openings, then up into the U (pic of it removed), then down and out thru the long sweeps.  The U was epoxied upside down to the top underside of the large tube, and fit around the end of the long sweep which protruded into the large tube and was glassed in after being inserted.

It is likely one of your U's came loose, mine were not on there very hard.

[Michigan boarder]

The new ends were from Centek Industries and are flame retardant, used in wet exhaust systems.  Mine are now 3.5" in and 3.5" out.  I glassed them in, then grinded down the sloppy stuff, then painted it up and installed it.  Pretty easy and fun DIY project.

I left the baffles out for more air flow, but installed STE's and I think it's actually quieter now than what it was before.  Behind the boat is has a gentle inboard rumble, sounds very normal.  This is our family boat so noise control was still very important to us.

 

 

 

[Shastasurf]

I took my muffler out and put straight pipes.   I haven't noticed it any louder but I do have fae.   I figured my muffler would fail at some point and just deleted it.

[pawter1970]

Nice work Michigan Boarder, thank you for the information, not sure if I can do this myself but will ask around to my more mechanically knowledgeable friends if they would take on that project.

thanks again.