exhaust question

bhale5

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Jul 8, 2008
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I have a 1971 merc 165 I6 that was converted to a trhrouh hull exhaust.I've never checked into this but I was wondering if there was some sort of muffler or noise dampener that can be installed that would quiet this thing down a bit.Thanks for any input.

Bryan
 

jerryjerry05

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Re: exhaust question

Is the old exhaust tube still in the boat? It might be as simple as replacing the hose that was removed. Got a pic? Jerry
 

bhale5

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Re: exhaust question

Yes it still has the old exhaust tube. The previous owner installed a turbo to the engine and ran the exhaust straight through the hull. Is there any reason why I couldn't just hook up the old exhaust tube or is it necessary for the turbo exhaust to be run this way.Thanks
 

Maclin

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Re: exhaust question

I think the turbo needs the free-flowing exhaust after it to work as intended.
 

79Glastron

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Re: exhaust question

Hold the phone there! You a turbo charger on your 165? I'd love to see pics of that. I believe they make a marine muffler that would work.
 

bhale5

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Re: exhaust question

I'll take some pics and postthem.It might be tomorrow,but just watch out for this post. I thought it might need that free flow but wasn't sure.It sounds like a champ, but if Icould quiet it down that would be cool.Thanks
 

bruceb58

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Re: exhaust question

The previous owner installed a turbo to the engine and ran the exhaust straight through the hull.

Really? I always thought you couldn't do that because of the heat.
 

79Glastron

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Re: exhaust question

I thought about this again, are you running water into the exhaust side of the turbo as well? I'm not sure how well that would work. I would think it would need cooling of some sort. I know large boats with turbo diesels must have a water jacketed turbo of some sort, right? Can't wait to see pics! Also, a muffler won't hurt turbo performance, or, not enough that you'll notice.
 

bhale5

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Re: exhaust question

Sorry it took so long to get back.Here are some pics of how its set up. Like I said this is how it was when I got the boat. All I know is it can really move on the water. I've never had a problem. At full speed it will go around 47mph on the gps. It will also yank up a 220lb skier with 5 adults in the boat with a 19p prop. No problem at all. Not sure who designed it, but it gets the job done. What's crazy is the engine is original, 37 years old.0709081828.jpg

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Maclin

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Re: exhaust question

That looks almost factory to me! Looks like it has been installed and running for a few years now. Does not look like much room for a muffler though, I see why you were asking now.
 

bhale5

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Re: exhaust question

I don't have any idea. I don't even know what a stock 165 runs like so I don't have anything to compare it to.
 

starsnstripers

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Re: exhaust question

Well I'll be damned! Aint that something.:eek: What make boat? Length? I have a 21.5 with a 1970 L-6 and i'm sure it would struggle with 5 people and a 220lb skier. :D It does look factory with the carb way to the front of the eng. like that. If i could find one of those setups i might skip putting my 283 in the boat and save it for another project. Geesh Bhale, doesn't look like much room for a muffler. If you could elbow it over, down, and out, maybe. You;ll have to search the market and see whats available. good luck with that. Where ya from Bhale?
 

bhale5

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Re: exhaust question

Its a 17' 1971 Century Raven. I didnt realize how uncommon this was. Is there any way to determine how many hp I'm actually pushing. I'm down here in athens, ga.
 

starsnstripers

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Re: exhaust question

WOW, 17' ? that thing must rip! I'm not sure about how much hp the turbo adds to 165hp. I'd be guessing that your approaching 190-200 but don't go by me i dont know the formula for it. Maybe someone on here could be of more help with that. Did you check those exhausts out that Bubba sent you on that link? I think you may be able to plumb in a muffler system with one of those setups. Good luck with it. I'm in Me. so guess i won't be getting a look at it from here, but the pics were great. If i come accross any info on them i'll let ya know.;)
 

bhale5

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Re: exhaust question

Yes, I saw those mufflers. I have about 2' between the exhaust behind the turbo and the exit at the hull. Do these quiet things down substantially. It sounds like a hot rod but a little less noise would make cruising a little better.
 

MikDee

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Re: exhaust question

Yes, I saw those mufflers. I have about 2' between the exhaust behind the turbo and the exit at the hull. Do these quiet things down substantially. It sounds like a hot rod but a little less noise would make cruising a little better.

Yes, It's like going from a straight pipe (no muffler), to a glasspack mellow sound.
 

hard-3

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Re: exhaust question

How about a corvair turbo muffler? i would think it would have to be wrapped in heat resistive insulation of some sort. I've seen some industrial engines that have a ceramic coating then covered in kevlar to insulate it. Unless it is water cooled I would think a regular glasspack would get to hot .
Jeff
 

MikDee

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Re: exhaust question

How about a corvair turbo muffler? i would think it would have to be wrapped in heat resistive insulation of some sort. I've seen some industrial engines that have a ceramic coating then covered in kevlar to insulate it. Unless it is water cooled I would think a regular glasspack would get to hot .
Jeff

No, no, I'm talking about the Primax round silencers, as in the link provided by Bubba 135.
 
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