Dry stack exhaust covers?

How do Nordhavn (and other dry stack boats) cover the end of the exhaust when they leave the boat to keep the rain out? In many cases, they are quite a distance up in the air.

Seen sawed off small boat fenders used. Must have climbed to get up there, or used some sort of stick.

I've seen buckets placed over them. I've seen fenders stuffed down into them. I've seen people do nothing. I assumed there is a flapper and a drain system inside of them.

I saw the 62 down in Indian Harbor beach and they had what appears to be a bucket over the top... Way up at the top. Perhaps a telescoping boat hook?

https://www.yachtworld.com/boats/1999/Nordhavn-62-3168900/Indian-Harbour-Beach/FL/United-States

Commercial fishing boats use a 5 gallon bucket or nothing.

Yup, bucket. If it's too high to reach you use a pole or boat hook.

If they are built right water will run down the outside shielding but can not get into the inner exhaust piping.

I cover mine with a piece of pvc pipe that has one end capped.
I used a railfitting and a piece of ss handrail tubing for a handle so I can place and remove it.
Spray painted the cover afterwards as the pipe was a bit rough looking .
My stack od was 4.5" so I used a piece of 6" pvc pipe.

Commercial boats with tall stacks use an automatic flapper that automatically covers the exhaust when the exhaust flow stops. Or a bucket. Enough rain can get into the engine.This one is made in the UK out of 316. Exhaust Rain Caps

An oval hole cut in an old gallon can works for us.


For summer layup we tape the exhaust closed , then install the can with a tie down , for hurricane season.

The flapper cap won't work in this situation since the end of the pipe is vertical, cut off at an angle facing the rear where the sheared edge is vertical and the pipe is about 45 degrees to the aft. Perhaps there is a rain drain before it goes into the muffler, but I would hope it didn't put the rainwater down the deck due to the teak decking below the exhaust pipe.

There was a can / bucket over the end while it was at the dock so I assume there is a way to cover it up when not in use. Probably a telescoping boat hook or something like that.

I once did an overhaul on an engine that had a vertical exhaust and the bolt in the flapper cap vibrated out, leaving the exhaust pipe collecting water which entered two cylinders. We replaced the two cylinders and did a top end overhaul on the other two. That engine ran over 50,000 hours after that. I have no idea how long it had run before that point...

Would a 90 or double 90 welded on the end cause a noticable flow restriction? Most of the boats I see down here use a bucket.