cracks in muffler
 

Hey guys I have some cracks in my muffler and needless to say especially when giving throttle it bubbles up at the cracks and leaks water into the boat. I got some bondo "professional glazing & spot putty" comes with a hardener. Can this be used on this muffler? I was going to fire it up on the hose and circle where the cracks were with a marker. Then dry it off good, sand it down and apply the filler, sand it down, then maybe do another layer. Should I then spray some kind of clear over it ? Or am I going about this all wrong? I really don't want to buy a new muffler but I cant have it leaking all over the transmission and getting more water in the boat then I need. Any other suggestions would be appreciated.

had the same problem with my boat a few years ago where the exhaust hose went onto the muffler and was clamped. i switched to the good clamps that use a through bolt type system vs the screw driven type and used a high temp silicon bead before putting the hose over the muffler and haven't had a problem since. I also double clamped the hose on each end. Be careful not to overtighten and crack the muffler more using those good clamps as they don't strip and can crush the fiberglass. If your leak is elsewhere then i'd imagine some more layers of fiberglass and resin might do the trick.

no the cracks are not where the clamps are, they are in other various spots. Im just wondering if I cant patch them with regular profession grade bondo, or if I need something different?

Beings it's got pressure going from the inside to the outside I imagine its not going to be easy to stop the leaks from the outside kinda like patching a tire. I realize there's probably less pressure in there than a tire though. All they are is molded fiberglass so if you're handy try marking the areas first then sand down some and try layering more fiberglass and resin on it. I don't have at experience w bondo putty but I suppose if it didn't work it could be sanded off and try something else. Try getting that putty wet after it dries and see what happens first though.

The muffler is a fiberglass tube that's wound in a few spirals. Depending on what kind of boat there may be a few tubes connected together with some fiberglass mat to hold it all together. Once you overheat it the resin melts out and your left with just raw glass. The leak you see in the outside most likely means the inside is begining to unravel somewhere. You can buy the tubes from Centek and cut any connectors or fittings off the existing muffler and put them on the new tube and have an almost new muffler or you can wrap the existing one with a few layers of new fiberglass and prolong it's life. If it's a DD with mufflers under the floorI would think seriously about the tube or buying a replacement. When a chep fix fails eventually you'll have a 3 in hole in your boat and it won't float long.

you can see some of the cracks in this first image pretty good. Im just wondering if this is patchable. I don't know why it wouldn't be. But If not I haven't been able to find anyone with a muffler that even looks like this. My main question is weather Bondo will work or not. I mean it is a fiberglass body filler. But not specifically for marine use.


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Pull the muffler off look inside, and if it looks like a rats nest (fiberglass has become unspun) then it's time to replace it. I just had to replace mine because it also had a crack that seemed to gradually grow. Where it was cracked, the fiberglass was also becoming soft. What is the make, model, and year of your boat?

It's a 92 Sanger 22fx direct drive with a merc 5.7, any idea where to find a replacement and cost?

Call the closest Sanger dealer and they can order the part directly from Sanger. If for some reason they don't have that muffler available you can have one made through these guys http://www.go2marine.com/category/14...for-boats.html. You can also call them at 800-998-9508. I lucked out and ordered mine through a dealer and had it shipped directly to my house. It cost me around $550 shipped. Twin Lakes Marine is probably your closest dealer....you can call them at 262-877-2462.

I wouldn't replace. I would try fiberglass resin and hardener from lowes and use the fiberglass matts with it and wrap up the entire muffler a couple times in it. Should be pretty strong after that

My 350 MPI Mag exhaust had a crack a few years ago. Fiberglass matting and resin did the trick. It was pretty easy to do myself and the repair has held up 9 + years with no problems...

I'd either repair what you have if you want a muffler or my preference would be to get some SS pipe or just exhaust hose and eliminate the muffler.

So i went with the matt/resin route. Made a good mess last night, but I think I got it done good. Didnt realized that paint thinner wasnt gona clean it up. lol... guess that paint brush is trashed. Ima sander it down and put another coat. That should hold, at least for this season hopefully.

Acetone is what's required for cleanup.

Get the cheap brushed at homer depot. And trash them. Save the good purdys for the hose

Do a couple layers of it. Should be golden after that