Help- Exhaust work with B31 in water?

[John F.]

I got all of Crows Nest's leaks except for one. It turns out that the starboard side fiberglass exhaust elbow--the elbow that transitions from vertical down to horizontal and out the transom--is cracked. The exhaust hose from the forward muffler to the elbow is too short, and the elbow cracked at that last inch aft where the hose slides on. Long story short, I want to pull up the starboard deck, take the elbow and hose out and replace with properly sized hose and an elbow that's not cracked (or f'glass up the elbow if that can be done).

To do this while she's still in the water, I'd need to plug the exhaust at the transom. She has a 5" exhaust. Is there anyway to safely do this so that I can work on the boat without it sinking, or do I need to get her hauled and do it out of the water?

Thanks

[CaptPatrick]

John,

Obviously, you can't sink if the boat's on the hard. That said, I've seen several boats with inflatable bumpers plugging an exhaust hole. Also saw a 47' Buddy Davis that sank when the bumper somehow became dislodged in the dark of night...

So yes, it can be done, but I wouldn't do it. Better safe than sorry.

[Capt.Frank]

John,
I have done it by placing a 5" fender in the exhuast and with bike pump it up to presure. I had to fix the exhuast get it welded. I did not sleep well that night. I also raised the hose above the water line and plugged and clamped the end. I would get everything ready if you do it in the water.
I have seen boats sink also trying something similar.

[mike ohlstein]

Some options...

http://www.mcmaster.com/#rubber-test-plugs/=riy71c


http://www.mcmaster.com/#tapered-rubber-plugs/=riy7hj

[captbone]

Nerf Football.

[bob lico]

A walk in the park! Go to plumbing supply house you want no hub cap. Just tighten on exhaust exit ----- waterproof or there are thousands of commercial dwellings in a heap of big trouble

[JimmyG]

Some options...

http://www.mcmaster.com/#rubber-test-plugs/=riy71c


http://www.mcmaster.com/#tapered-rubber-plugs/=riy7hj

Gota love Mcmaster Carr they have it all

[mike ohlstein]

They cost a few dollars more, but you have it the next day.

[Pete Fallon]

JohnF,
I've done it will all the mentioned type plugs, nerf ball, rubber plumbing end caps, fenders. I have just let it sit in the soft mud in Juniper Cove in Salem Ma at low tide. You can get the yard to let you hang in the slings while the crew goes to lunch, that way you don't need to be blocked and jack standed. The safest way is out of the water, that way you can check the condition of the zincs and other underwater metals and your cutlass bearings.
Pete Fallon

[Carl]

Capt Pat is right, but never overly exciting that way....
and can't say can't either...we had quite a few boat sink on land here a couple years ago.
A bit outside the norm...but does happen. Sorry, being an instigator.

When I had to pull my risers, when I had to reglass the muffler, before I realized I had to glass the muffler, I stuck a Pipe cap over the exhaust outlet and raised the balance of exhaust hose above the water line inside the boat, another time added sticking a plug in the hose and tightened with hose clamp to secure.

http://www.amazon.com/Mission-Rubber-Ba ... B007QCW5KS

[bob lico]

Thats it carl in the trade called " no hub pressure cap" on multi million doller homes the plumbing contractor installs the no hub pressure cap on the roof vents then pressure rise the waste system with air with gauge must hold pressure for 24 hours .this procedure is to avoid tearing down ornate ceiling afterwalds . I use them every winter to prevent cold air going into open exhaust valves with block heater on 7/24. Last year prevented the hurricane water going up the exhaust because boat was chained down. Not only are they a foolproof system the caps can take quite a bit of pressure

[Joseph Fikentscher]

For short term repairs I have used Nitrile gloves to keep the water out. Just place them over the exhaust. They will stop the water from entering. I usually place three gloves on to ensure a seal. I wouldn't use this method for long term protection but it works in a pinch. Keep a wooden plug available in case you need it in an emergency.

[John F.]

Thanks for all the advice and warnings. I'll let you know what I decide to do.

[IRGuy]

Back in my sailboat days I owned a wooden 34' sloop. Every spring launch she leaked lots until the wood swelled.. I always slept aboard the first night.. just to be able to hear my high bilge water alarm. A friend with a similar boat but no alarm claims he slept the first night with one foot on the cabin floor.

[Mikey]

John,
If you have enough exhaust pipe sticking out of the transom put a piece of rubber (inner tube) over the pipe and hold with an exhaust hose clamp.

[Rawleigh]

+1 on the No Hub Bob suggested.


Home Depot would have them.