Cutting lip off the muffler

[bclery]

I found my muffler had come lose from the wood mount and the wood mount lose from the hull.  So I ripped the mess out and will refurbush and re-install.

I found that it was a very tight fit getting the muffler out and without the wood base being lose I am not sure I would have gotten it out.  I took it out behind the engine over the shaft.  My goal is to improve this so that the muffler can easily be removed and installed.

I see no purpose for the lip around the bottom of the muffler.  Four decent SS bolts will hold the muffler in place as well as that lip.  I plan on cutting the lip completely off so that the muffler bottom is smooth.  I believe this will make installation/removal much easier. 

I expect to re-pressure test the unit after the cut.

Has anybody done this?  Just wondering.  Inspecting the unit I can't see how this cut would really damage the joint.

Also, is there any value in re-coating the inside of the muffler?  Maybe slosh about some acitone to clean and then slosh about some good paint.  Anybody done that ?

[Stu Jackson]

Ron's removed his muffler, so I can't add anything to that.

Cleaning the inside makes no sense, 'cuz it's just gonna get filthy all over once you run your engine.  Bet you have other better things to do.

[Ron Hill]

Bill : You're reinventing what I did over 12 years ago!  You need to look at those old Mainsheet tech notes.
Basically I made a thicker piece of plywood that fit inside the lip of the muffler and attached that plywood to the 2x4 stringers glassed to the hull.  Be VERY careful screwing around with that lip of the muffler so you don't break the seal of the muffler top to the bottom!!  

I found my stringers were loose and some bright finishing nails in the factory installation !?!  I re-glassed them and used all stainless fasteners.  

Read read read - it's all been done before!!   A thought

[scotty]

I recently took my muffler out (to put in a new one).  It really didn't take to much to come out through the access hatch because I had the exhaust disconnected from the engine.  This may not help your situation, but it worked out well for me.

[Stu Jackson]

Bill : You're reinventing what I did over 12 years ago!  You need to look at those old Mainsheet tech notes...

Read read read -

Read it here:  http://www.c34.org/mainsheet/pdf/Nov-2001.pdf

and an old FAQ:  http://c34.org/faq-pages/faq-muffler.html

I got these easily by doing a ctrl-F search on the Knowledgebase -  go to C34 Tech Notes at the top, and use the Knowledgebase spreadsheet.

BTW, when you use the Knowledgebase, the spreadsheet downloads to your computer, so you can search all day without needing internet connections, PLUS, once you get back online, the Knowledgebase LINKS work to get you right to the contents.  Using ctrl-F on the spreadsheet is very easy.

[bclery]

Thanks for the input.  I did read all that stuff, but I did not see anyone cut the lip off the muffler.  With the exhaust in place I had a very tigh fit getting the think out, so I wanted to remove that lip.  Also removal of the lip will allow easier placement of the muffler even after the wood strucure is expoxied in place.

I started cutting into that lip last night and now I see how it was manufactured.  I believe there is no risk of leak by cutting the lip off.  From what I can see the lip is NOT where the joint is.  I believe a simple flat glass bottom was originally pushed up inside the lip; the lip is just a part of the top continuing down.

I'll let you know how it goes.

[Stu Jackson]

Pictures'd be really nice, 'specially of the cut you made in the lip.  All the best on your project.

[Ron Hill]

Bill : Glad to hear that your cutting off the lip went OK.  I hope that you are correct that when you pressure test it that the seal was not violated.
   
If all is OK you'll be lucky, as Catalina makes their own mufflers and double pressure checks them.  Once after they are made and again after the corner holes are drilled!!! 
I checked on this when I redid mine.     

[Mike and Joanne Stimmler]

I'm confused, aren't the mounting holes part of that lip? What will you mount it to without the lip?