Muffler repair Q
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Boat Maintenance
Forum Discription: Discuss maintenance of your Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=24108
Printed Date: November-19-2024 at 5:39am
Topic: Muffler repair Q
Posted By: rfarkash
Subject: Muffler repair Q
Date Posted: November-11-2011 at 2:57am
|
As part of my winter "once over" on my new boat (1989 SN)I removed the invertaflo muffler to replace the 4" exhaust hose and the riser hoses. One of the tubes on the muffler that connects to the riser has some delamination I want to fix. I am a newbie to fiberglass repairs so please excuse the ignorance in the following question. What type of glass do I need? A search on the forum recommended epoxy resin vs. poly, but no mention of glass type. Assume some cloth, but clueless as to thickness, weave, weight, etc. I think the trick will be getting the final diameter correct so the 3" hose still seals. Am planning on cutting off the tube almost flush with the main body, then using a can as a form to wrap around, but am open to other ideas if you have them.
Thanks Ron BTW, this whole boating thing is taking way more time and money than I though. Boat was running great the few times I had it on the water after I bought it, but now it's in pieces in my garage with boxes from skidim around it  and I'm spending hours reading the forum. 
|
Replies:
Posted By: SNobsessed
Date Posted: November-11-2011 at 10:54am
|
Ron - I did a similar repair on my invertaflow. I just used some generic cloth I got at wallys. I would not cut the tube off. I recommend just grinding the delaminated part back until you get to solid material & tapering it out to a very shallow angle. Using a cylinder of some sort as a ID form is a great idea. After you get it built up, just sand it back to the correct OD.
Use epoxy resin, of course. The whole boat thing is definitely a major hobby - it is good that I store it offsite 8 months of the year so I focus on other things too! ------------- “Beer is proof that God loves us and wants us to be happy.” Ben Franklin |
Posted By: TRBenj
Date Posted: November-11-2011 at 10:57am
|
I would not cut that entire 3" inlet section off. Just grind off the delaminated outside layers. Not sure if the black is paint or gel (most likely paint) but you'll want to remove it from the areas that you will be re-glassing in order to get good adhesion.
As far as glass goes, http://uscomposites.com/cloth.html - US Composites is a popular place for supplies. I would repair that section with ~5 layers of alternating mat and cloth, starting and ending with mat. 4oz or 6oz E-glass will work just fine on the cloth, and the 1-1/2oz chopped strand would be fine for the mat. Make each layer slightly larger than the last. ------------- |
Posted By: Morfoot
Date Posted: November-11-2011 at 12:19pm
|
Ron, you don't have to remove the tube to fix this. Repair the original one. It's not that bad and can be fixed. You want to use a thin satin or biaxel weave cloth as it will be able to conform to the complex curves of the muffler. Thicker cloth tends to lift up easier.
Cut out a section of a used juice can, coffee can, large vege can, or metal duct work to use as a form. Before you insert it into the tube place a sheet of wax paper between it and the wall so it won't stick to it. If the flange is weak and damaged then add a little resin to the damage before inserting your "backup form" I'm gonna disagree with my fellow CCFans and say you don't have to grind out the delaminated plies until you hit solid. We do this sucessfully where I work by doing the following.... Prep the ouside wall of the damage my sanding it lightly, removing the black paint, then wipe it down with acetone to be sure it is free from all oils before you start. Mix up your resin then set it aside. Heat up the damaged area with a hairdryer and get it as hot as you can. Doing this will enable the damaged plies to wick up the resin and will flow deep into the damage getting better penetration and a more solid repair. Then start brushing in you resin being sure you soak it in everywhere. Once you have thouroughly soaked the cloth with resin, use packing tape (clear or brown tape) and wrap the tube with it pulling it as taught as you can to compress the delaminated layers against each other. ( hince reinforcing the inside with a metal sleeve) Wrap it up as tight as you can being sure you fully encapsulate the entire damaged area. Once it cures remove the tape and lightly sand the tube. Coat the tube with resin then add a couple of repair plys going totally around the tube. Start and stop your repair plies in different areas so that you won't have a concentrated weak point at the seams. You'll want to overlap each ply about 1/4 of an inch. At this point leave the form in the tube and rebuild the flange damage if you need too. I'd wrap it at least twice then cure it. Lightly sand it then paint it and reinstall. Let us know how it goes and post pic's of your repair so others can learn. Good Luck! ------------- "Morfoot; He can ski. He can wakeboard.He can cook chicken.He can create his own self-named beverage, & can also apparently fly. A man of many talents."72 Mustang "Kermit",88 SN Miss Scarlett, 99 SN "Sherman" |
Posted By: rfarkash
Date Posted: November-11-2011 at 10:39pm
This site is AWESOME 
Just the kind of info I was looking for. Looks like another order is in order. Hopefully I can stay away from the monster tower site - feeling the need for elevation next year... Thanks Ron |
Posted By: rfarkash
Date Posted: April-14-2012 at 5:36pm
|
Finally in last stages of spring tune up and last thing to do is tackle muffler repair. After trying to sand/grind delam, found out it was pretty much fried - breaking apart and with gaps. So I cut the tube off and left about 1" that was good to bond to. Plan is to put a metal pipe to act as a mandrel and build up glass around that. Leaving metal pipe in for extra strength and so this doesn't happen again in the future. Went to autozone and picked up a 2.5" ID exhaust pipe which measures 2 3/8" ID, but original ID of glass tube was 2 5/8. Think I'm being anal, but will 1/4" difference make a difference in backpressure that might affect performance? Will post pics soon. Thanks Ron |
Posted By: SNobsessed
Date Posted: April-15-2012 at 12:20am
|
Ron - A car exhaust is much smaller. I think the back pressure won't be affected much. I would wrap the pipe in plastic & pull it out after the glass sets. If you do goodf layup it won't fail again. ------------- “Beer is proof that God loves us and wants us to be happy.” Ben Franklin |
Posted By: rfarkash
Date Posted: April-15-2012 at 2:04am
|
Any issues leaving it in other than the slightly reduced diameter? Would feel better with some metal in there to resist the clamps... Thanks Ron |
Posted By: SNobsessed
Date Posted: April-15-2012 at 11:22am
|
What material will it be? If 304 SS then OK. 409SS will rust up eventually. Rust expands, & could cause the glass to crack, just a guess though. ------------- “Beer is proof that God loves us and wants us to be happy.” Ben Franklin |
Posted By: rfarkash
Date Posted: April-15-2012 at 12:41pm
|
Pretty sure it's not 304 since I got it at Autozone cheap. It is exhaust tube so assume aluminized steel, but good point that it will likely eventually rust. Anyways, here's where I'm at currently. Thanks Ron 
|
Posted By: 8122pbrainard
Date Posted: April-15-2012 at 1:46pm
|
Ron, What's the white stuff you are using? I sure hope it's not Marine-Tex. The repair should be made with epoxy resin and fillers when needed. BTW, I agree with Chris. Use the pipe as a form and then get it out of there. Some will use a beer can! ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: rfarkash
Date Posted: April-15-2012 at 4:35pm
|
Nothing added - white is just where I sanded as prep. Guess I'll have to go buy a 6 pack of cans now :) Thx Ron |