Strange debris in exhaust pipes

[56MYHATTERAS]

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[56MYHATTERAS]

Greetings. Sorry i didn't post the question I'm asking. This is a 56MY that's been out of the water since October and was stored indoors. The boat made a 90 mile cruise from home port to storage and sat in the water for about 3 weeks. She's not in the water yet this season and I visited her yesterday and looked down the exhaust ports. They were both filled with this combination of what looks like hair, wool and zebra mussels. It pulls out, some easily and some like it's attached to the pipe. Is it muffler packing or a vermin's nest? The marina is baffled. Any thoughts?

[doc g]

Muskrats or river otters...........make sure they have not chewed holes in the exhaust system. I had an issue earlier this year with one that ate thru a hump hose. My neighbor was not so lucky, they ate thru his exhaust got inside the boat had babies and proceeded to eat everything that was not metal including headliner, furniture, upholstery, all the wiring to his fly by wire Volvo diesels and other god only knows what else. Then they died inside the boat. It's been a year and half and the boat is still not able to be used. He would have been better off had it sunk as his insurance will not pay for any of the damage. I've heard they've spent over 200K trying to fix it. I now have stainless steel colanders wrapped in rubber jammed in my exhaust. We tried using inflatable fenders and the critters just ate right thru them ............Make sure you check the boat when it is put in the water , the boat next door had a stainless steel mixer eaten thru also............................Pat

[SEVEN]

That’s a first for me but it sure does look like a nest. Make sure that critter is out before you fire up.

[kingsley_oasis]

Mine did the same. 12v71TI's.
The rear short section of my mufflers is about 12" in from stern, and was just a tube within a bigger tube, between which was some packing which looked like glass wool. The inner tube was very thin, and had lots of slots in it which partially broke up.
Odd they would go at same time. I lost one, but other had failed before I got the boat.
I checked external wall and end pipes and they were solid. Still good four years latter.

[SKYCHENEY]

Around here they have muscrat shooting contests; as in, how far will the muscrat fly out of the exhaust when you fire em up.

[Chasemmc]

Had the same issue on my 56. Plugged exhaust with plastic buckets, but chewed through. Went with galvanized buckets wrapped in rubber door weather stripping to create tight fit. Seems to be working.

[SKYCHENEY]

The permanent solution


https://hurleymarine.com/shop/muskra...xhaust-guards/

[Chasemmc]

Buckets. $20

[SKYCHENEY]

made my own for $25