exhaust flap

[coddock]

So I noticed today after returning from a day offshore that my exhaust flap was gone. I notice that some boats don't have them. The type I had was a flange with a hinged flap;not the clamp on style.

My questions are...1.is it absolutely necessary to have one?
2.Can I install a simply rubber flap,screwed to the transom
above the exhaust outlet?

It appears to be a fairly difficult job to replace the flanged outlet,not to speak of the haul out.

 

[captchuck]

I know that on both my boat and my fathers one gas the other diesel we do not have them.

 

[F/V First Team]

no you don't have to have one, some people like them (dont ask me why)
most replacement ones go on with a hose clamp, no screwing needed. it could be put on while in the row boat, no haul out that way

 

[MDI45]

Your transom will stay a little cleaner without it also

 

[Stinkpot]

Probably don't need one as long as you have adequate slope of your exhaust from the engine to the transom. Having a surge tube in your exhaust should also exclude the need for the flap.

If you tend to fish areas like The Race and your transom gets slapped with three footers while drifting into the rip, it'd be a good idea to put one back on.

Stinkpot

 

[Bulman711]

I know that I need one in my JC. If I dont have it and take water in the exhaust it stalls the engine out... Something to make sure of before going without.

With that being said if you just noticed, and have not been having a problem then you probably do not need one.

 

[steveinak]

lots of the jet rigs up here use a piece of car or truck inner tube hose clamped over the exhaust. They tend to take a big glup of water up the exhaust when they run aground doing 25/30 knots, as the saying goes " if you can see the seagulls legs your in deep shit, as long as their floating your good to go".

 

[F/V First Team]

I hear that
Somewhere I have a photo of a seagull standing on top of the water while we were in 70 feet.
Ledges have no sense of humor up here

 

[coddock]

Update...First and foremost...Thank you all for the intel.Very informative and knowledgeable people here!

So,as stated here,the jury is out as to whether or not I need the flap.It seems to depend on the specific build;engine height/exhaust outlet height ratio,etc. I am thinking it won't hurt,good insurance.

Secondly,the part is made by Centex. It is a two part piece.Internal piece with flange fastened to transom,and external extension piece with hinged flap.
Now the surprise...The external piece is actually glued (5200) to the flange.

So....I guess a haul out to dry out fitting and allow 5200 to cure.

Does anybody have any crazy ideas to get the transom up 6" or so to allow me to do the repair without the haul out???

 

[Regina E]

Siphon all your fuel to one side and get a load of junk on that side too and leave it till cured.

 

[steveinak]

Update...First and foremost...Thank you all for the intel.Very informative and knowledgeable people here!

So,as stated here,the jury is out as to whether or not I need the flap.It seems to depend on the specific build;engine height/exhaust outlet height ratio,etc. I am thinking it won't hurt,good insurance.

Secondly,the part is made by Centex. It is a two part piece.Internal piece with flange fastened to transom,and external extension piece with hinged flap.
Now the surprise...The external piece is actually glued (5200) to the flange.

So....I guess a haul out to dry out fitting and allow 5200 to cure.

Does anybody have any crazy ideas to get the transom up 6" or so to allow me to do the repair without the haul out???

couldn't you back up to a floating dock and install a flapper with a hose clamp?

 

[coddock]

couldn't you back up to a floating dock and install a flapper with a hose clamp?

I wish it was that simple ! The set up I have has a flange mounted to the transom.The flange is for all intent and purposes flush with transom with no protrusion to clamp to.The repair part is the extension and flapper.

I an docked @ a slip,but the exhaust is half,give or take,in the water. I have to get it out of the water to dry,clean,and install new part. Looks like a short haul is the only game in town !

 

[JimRP31]

I wish it was that simple ! The set up I have has a flange mounted to the transom.The flange is for all intent and purposes flush with transom with no protrusion to clamp to.The repair part is the extension and flapper.

I an docked @ a slip,but the exhaust is half,give or take,in the water. I have to get it out of the water to dry,clean,and install new part. Looks like a short haul is the only game in town !

First, How big is the you boat? I think with anything 30' less you could just pile as much of your moveable weight forward until the transom is out of the water. Anchor, fishing gear, beer buddies, anything to get the stern out.

 

[coddock]

First, How big is the you boat? I think with anything 30' less you could just pile as much of your moveable weight forward until the transom is out of the water. Anchor, fishing gear, beer buddies, anything to get the stern out.

28 foot...I think ??? it would take some serious weight to get the transom up. Beer buddies??? for the few hours,I need for 5200 to cure;the way my buddies drink beer...oh boy,much cheaper for a short haul !!!

 

[steveinak]

get some of that 2 part epoxy that cures under water. we used to use splash zone i think its made by pettit.

 

[coddock]

Steve,great idea ! I will look that stuff up. I would imagine it is "A" o'k for fiberglass ?

 

[steveinak]

Steve,great idea ! I will look that stuff up. I would imagine it is "A" o'k for fiberglass ?

I used it on my bowpicker to fair net hanging rough spots and to fill gouges that my anchor dug into my bow. You mix/kneed 2 equal parts in a bucket of water and then just spread it on and smooth/fair it out with a vinyl glove dipped in water. They used to patch holes and cracks in boats that had whacked rocks.

 

[BillD]

28 foot...I think ??? it would take some serious weight to get the transom up. Beer buddies??? for the few hours,I need for 5200 to cure;the way my buddies drink beer...oh boy,much cheaper for a short haul !!!

Maybe best just to haul it and "do it right" by replacing the flange.
Shortcuts always seem to comeback and haunt ya!

FWIW,

Bill D

 

[coddock]

Maybe best just to haul it and "do it right" by replacing the flange.
Shortcuts always seem to comeback and haunt ya!

FWIW,

Bill D

Ya,I hear ya! I am leaning just that way.The only short cut I am presently pondering is fastening a rubber flap on the transom,over the exhaust. That would at least save me the haul out till I had her on stands in the fall. Any opinions on that?

 

[hntrss]

I got the exhaust of a 42 Torres out of the water with a couple of 55 gal drums of water on the bow. I did an in water muffler replacement. No issues whatsoever. It can be done.