Muffler Replacement

[doc g]

I've got a muffler which appears to have "blisters",has anyone replaced a muffler in a 61' CPMY/MY .It can't be removed in one piece without destroying a lot of nice cabinetry . I was considering coating the whole thing in West system or possibly cutting it in pieces to remove then replacing with 2 or 3 smaller mufflers . Any suggestions greatly appreciated!

[Nonchalant1]

Is it the big fiberglass muffler in the aft stateroom? Hatteras is famous for blisters on the fiberglass boat bottoms, so could it be just an exterior cosmetic thing? For a bottom job, they "peel" the fiberglass and recoat. Maybe you can sand down the blisters and see if there's good fiberglass under the blisters, so they're just cosmetic?
It's be a shame to replace something that's OK. Of course, it'd be a bigger shame to not replace it if there is a real problem that needs to be fixed.

Doug Shuman
1978 53MY

[doc g]

There is 'salting' on the surface of the muffler which reappears after being wiped away . I believe it is indeed osmotic blistering as there are more on the lower part of the muffler than the top. I.E. osmotic blisters happen more in warm water . And yes , it is that big sucker that lurks under the freshly redone cabinetry in the MSR , and Corian counter top in the aft head of my boat.

[rtrafford]

if the exterior of the mufflers are blistering, the water is undoubtedly coming from the inside of the beast. my recommendation would be to cut them out and replace them with straight exhausts before i would sequence smaller mufflers in their place. most aren't designed to work like that, and it's quite likely that you'll go through a lot of work merely to create a poor environment for your engines due to backpressure.