Exhaust Flappers

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Dug
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Exhaust Flappers

Post by Dug »

Hi all,
Alchemy is getting ready for the first phase of her exterior makeover up at Brewer Street Boat works. She won't entirely know what hit her over the next year and a half or so. Skip and I were going over some pictures yesterday and discussing the faired in fiberglass exhaust exits on the transom compared to the metal flanges of the style that are currently there as a factory installation. He thought the faired method was pretty cool and thought it worth pricing.

My question is this. Many of the engine oriented people in my life have advocated very strongly that I use exhaust flappers. I have done so since the repower without any hesitation. They are black rubber and slide over the exhausts on the exterior of the transom to keep water from backflowing into the exhausts, primarily on the drift I assume. If we do the new exhaust exits, not only with the flaps not be particularly pretty to look at now that the boat looks pretty, but there will be nothing to attach them to.

So those who have the faired exhaust outlets (like you Jimmy G!) what do you do about flaps? Do you use them? Have the been recommended for you like they have been for me? Any thoughts?

Thanks in advance.

Dug
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Pete Fallon
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Re: Exhaust Flappers

Post by Pete Fallon »

Dug,
If you go with the fiber glassed outlets you don't need the black rubber flappers, but I would add( if you don't already have them) surge tubes into the exhaust system. The flappers are there to prevent water from entering the exhaust tubes when backing down hard on a big fish. I am a traditionalist and like the flapper system I have them on 5" stainless steel outlets attached to FRP exhaust tubes with Vernay mufflers and 3" exhaust risers on the engine exhaust manifolds all connected with blue silicon hoses. If you go the glassed in look make sure that there is a flexible section of hose between the outlet and the exhaust tubing, if none there your going to have cracking around the transom from vibration that is transferred via the exhaust lines.
Pete Fallon
1961 Express Vizcaya Hull 186 12-13-61
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TailhookTom
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Re: Exhaust Flappers

Post by TailhookTom »

Dug wrote:Hi all,
Alchemy is getting ready for the first phase of her exterior makeover up at Brewer Street Boat works. She won't entirely know what hit her over the next year and a half or so.
What the heck are you doing to her? She was built in 7 weeks, year and a half??????? I know I had mine in a shed for close to 24 months, but that was because this cheap Connecticut yankee was doing the work himself -- are you going to get fiberglass dust in places normally reserved for more pleasurable activities? Seriously, good luck, it will be worth it in the end.

Tom
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Dug
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Re: Exhaust Flappers

Post by Dug »

Tom,

Multiple phases, not all at once. budget ya know? It comes back to being a bit of a yankee. Now Tom, answer that question about the flappers if you are chiming in! Pete did a great job! ;)

Thanks!
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CaptPatrick
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Re: Exhaust Flappers

Post by CaptPatrick »

Dug,

Flappers: They work... They're butt uggly... I hate the pop-pop noise they make... If you decide to stick with them, don't waste time & money glassing in exhaust ports.

I wouldn't have them on my boat & have never put them on a customers boat. Talked a couple of customers into removing them though...

But if you want that sexy glassed in look, (I would), install surge tubes, and a baffled muffler, (if you don't have them already).

http://www.bertram31.com/hancock/eng_cmpt/engines/exhaust/

Image
Br,

Patrick

Molon labe
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TailhookTom
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Re: Exhaust Flappers

Post by TailhookTom »

Dug wrote:Tom,

Multiple phases, not all at once. budget ya know? It comes back to being a bit of a yankee. Now Tom, answer that question about the flappers if you are chiming in! Pete did a great job! ;)

Thanks!
Dug:

I know nothing about flappers, nor inboards, nor exhaust tubes -- remember, my new motors start with YA, but then they add a MAHA to the name, not a NMAR.

Yeah, I know the drill of doing it in stages, however, I got killed by the "Inactive" storage charge -- I hadn't budgeted for that. Make sure you review that piece of the agreement -- it was 3 times what monthly storage was.

Tom
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Re: Exhaust Flappers

Post by keysdisease »

Dug wrote:Hi all,
If we do the new exhaust exits, not only with the flaps not be particularly pretty to look at now that the boat looks pretty, but there will be nothing to attach them to.
Dug
It would not be difficult to use the flappers only from the store bought units and install internally in the pipe a few inches from the end. Glass in a little clamp on the top inside a few inched in from the end to accept a couple of screws.

We do internal flappers on some of the larger systems we make, so I'm not inventing the wheel here.

Steve Moyer
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Gert van Leest
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Re: Exhaust Flappers

Post by Gert van Leest »

Dug ,

The only way to go is the Captains way.!! forget about the flappers.

Gert
Women are like boats ,the older they get , the more money and professional help they need to look beautiful.
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Dug
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Re: Exhaust Flappers

Post by Dug »

Flappers are gone. In fact, so are the exhaust flanges! LOL...

I believe I have picked out the hull color, bootstripe color, and bottom should be in process of being stripped as we speak. At least it should have been done earlier today.

This is a whole new experience for me. :)
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TailhookTom
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Re: Exhaust Flappers

Post by TailhookTom »

What are you barrier coating it with? Your neighbor at LBI has some pretty cool stuff now.

Tom
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Dug
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Re: Exhaust Flappers

Post by Dug »

Interprotect
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TailhookTom
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Re: Exhaust Flappers

Post by TailhookTom »

Check this out too:

http://www.lbifiberglass.com/POLYGELCOA ... arriercoat" onclick="window.open(this.href);return false;

Tom
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Gert van Leest
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Re: Exhaust Flappers

Post by Gert van Leest »

Dug wrote:Interprotect
wise decision !

easy to aply and and proven to be good !

Gert
Women are like boats ,the older they get , the more money and professional help they need to look beautiful.
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