Water Muffler Box Leak

[Piratenorm]

I have a 1983 Mk 1 Catalina 30 with a persistent leak around the water muffler box. It causes the bilge pump to cycle through a discharge about every 5 hours. That is enough to cause me concern because, as we all know, it ain't gonna get better by itself. I know nothing about what the box contains inside. I see it is an upended fiberglass housing attached to a lid by several screws and what looks like butyl tape sealing it. Does the boat need to be hauled to work on it? Is it most likely just the seal that is leaking or a clamp on a hose inside? How involved is it to get the lid off, considering all the hoses and wires crossing it under the galley cabinet? What should I do about the leak? Should I even be concerned? As she's 29 years old this year (hull 3335) is it something I should do a major renovation on at this time? It is a drip leak in the most inaccessible place possible, although I could add additional fiberglass mating formed around the base to seal it better.
Thanks. Norm

 

[rbmcintire]

You do not have to haul the boat and the muffler unit is permanently sealed, one hose in, one hose out. New ones are about $350. On our '84, I decided to try a repair before going with a new one but there are warnings about doing this. If you do decide to replace or work on it, you have to pull the galley cabinet. I also ended up replacing the engine exhaust piping. You might decide yours probably needs it too after 29 years. Just duplicate the existing pipe nipples and fittings. There's previous threads here if you do a search. Good Luck.

Rob

 

[Stu Jackson]

Here's a link which includes the earlier discussion here:

http://c34.org/bbs/index.php/topic,6728.0.html

 

[Jimm]

I have a 1983 Mk 1 Catalina 30 with a persistent leak around the water muffler box. It causes the bilge pump to cycle through a discharge about every 5 hours. That is enough to cause me concern because, as we all know, it ain't gonna get better by itself. I know nothing about what the box contains inside. I see it is an upended fiberglass housing attached to a lid by several screws and what looks like butyl tape sealing it. Does the boat need to be hauled to work on it? Is it most likely just the seal that is leaking or a clamp on a hose inside? How involved is it to get the lid off, considering all the hoses and wires crossing it under the galley cabinet? What should I do about the leak? Should I even be concerned? As she's 29 years old this year (hull 3335) is it something I should do a major renovation on at this time? It is a drip leak in the most inaccessible place possible, although I could add additional fiberglass mating formed around the base to seal it better.
Thanks. Norm

Sealed unit - replace it. I just replaced mine (1993). It's not a complicated task. Bildge stays dry now. When I removed the old one it had a hole in the bottom and I haven't a clue how that could have happened.

 

[jrowan]

If you think about all that corrosive, steaming hot soot laiden waste water that runs out the engine block & mixes with the diesel exhaust its really not hard to imagine that it could create a corrosive tonic that would eventually eat through anything. I was lucky that mine has already been replaced. I would think that the hardest part is getting off the galvanized pipe threaded steel fittings, such as the exhaust mixing elbow that will be rusted together pretty good after 30 years. I don't even think that PB Blaster can break a bond like that. It may have to come apart with a hack saw. Good luck.

 

[Stu Jackson]

I would think that the hardest part is getting off the galvanized pipe threaded steel fittings, such as the exhaust mixing elbow that will be rusted together pretty good after 30 years. I don't even think that PB Blaster can break a bond like that. It may have to come apart with a hack saw.

Actually, it's quite easy. The exhaust riser attaches to the back of the engine manifold with three nuts on studs. The real b&itch is getting that bottom nut off!!! Took me a week of PB Blasting and a lot of leverage. Beware of PB Blaster near the transmission seals, they do not mix.

 

[Piratenorm]

Thanks to all. I'm gonna do more research and live with it this season, less than 2 months now till we haul out for the winter (sniff...) and there's too many new places to see to get bogged down with another lengthy project. Just replaced the bilge pump as a matter of safety and I'll do the work when she's on the hard, including re-routing all the stupidly placed plumbing lines under the galley sink so I can actually have some under counter storage for cleaning supplies. Again, thanks.