[C320-list] Muffler leaks and drainage

[Graeme Clark]

Last summer, after motoring any length of time, we would get a diesel fuel smell in the aft cabin and  - i noticed  also - more strongly under the galley sink.
I know I don't have a fuel leak and I know that the exhaust system is good as far as the muffler.

I therefore am assuming either a leak from the muffler or from the exhaust hose itself, which is I think the original fit from 20 years ago and therefor probably perished!

So I will be replacing the exhaust hose and have removed the muffler to inspect at home. There is no immediate obvious sign of a leak but it isn't under any pressure, of course. Any suggestions as how to best test it?  Even if it isn't leaking I thought I might take the opportunity whilst out of the boat, to reinforce any weaker areas with glass mat and resin. But what ARE the weaker areas? I know others here have had problems with these mufflers on and off over the years.

Finally, there is what i assume to be a T-shaped drain tap on the side of the muffler, but I was surprised to find it in the fully unscrewed position (in other words fully counter clockwise). has it vibrated open, is that the ‘leak' - or does this drain valve work in the reverse sense to ‘normal’?

Thanks in advance for any guidance

Graeme
#366, 1996, Oskar, Falmouth UK

———————————————————
I work irregular hours and often write emails late in the evening and at weekends; that doesn’t mean I expect you to do the same; reply when convenient!