Transom exhaust outlet options ??

BillD

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I am increasing the exhaust diameter from 3 inches to 5 inches.

The 25 T Jason has an 8-9 degree stern angle. The 3" bronze exhaust flange I removed is 8 degree offset. Meaning the 3 inch pipe out the back is level with the water line.

Item # 70te300, Transom Exhaust Fittings On Buck Algonquin.

Going to a 5" cast bronze exhaust flange (or stainless) the choice is a 90 degree (flat) flange. Meaning the 5" outlet will be 8-9 degrees pointing down and the inside pointing 8-9 degrees up. No good in my book.

OK I think I have two options. Install the 5" straight flange with an 8-9 degree shim wedge on the outside of the hull keeping the exhaust outlet level with the waterline....or a piece of straight 5" fiberglass exhaust tube and glass it into place on the inside and fair and gel coat the outside with no flange.

Either way I don't want the final install looking "cosmetically hokey" :eek:

Show me your pictures of your transom exhaust outlets please !!

Or help me locate a 8-9 degree 5" exhaust flange..bronze, stainless, fiberglass.
Or a 5" O.D. trim ring would work. :D

btw, I spoke to Buck Aloquin directly, all that is available in 5" is straight.
No offsets either inside or outside.

Appreciated, Bill D

IMG_1830.jpg
 

petrel

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Figured you'd go to 6" for all that power.
 

Keelboater

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I made the 2" water outlets for the stern of my Bertram out of stainless. (It has a side outlet for the exhaust gasses with only water outlets at the transom) The pipe is horizontal to the water line, and the flange was fit up against the transom and tacked in place for correct angle. Then removed for TIG welding and polishing. Not nearly as bad as it sounds. Looks great. The pic isn't that good because I cropped a shot from far away. But it gets the point across.

Bertram Exhaust.jpg
 

plowin

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Have one fabricated out of quality stainless at whatever angle and offset you like and have it polished up, piece of cake. Never liked the fiberglass tube sticking out of the transom, I have seen them chewed right off by debris on an outgoing spring tide in the river once something fetches up on it, like a tree or someones deck!
 
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cb34

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outlet

Bill, my 30 just has the 6" tube extending out the back with a flap. Only thing visible is the flap, very simple;)
 

BillD

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OK,

Who do you suggest to "fabricate" a 5" 8 degree offset exhaust flange.

Also, this rehab/repower is a "low budget" project.

What do you figure the cost will be.

Polished stainless of course.
 

Keelboater

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OK,

Who do you suggest to "fabricate" a 5" 8 degree offset exhaust flange.

Also, this rehab/repower is a "low budget" project.

What do you figure the cost will be.

Polished stainless of course.

a) How long does the 5" O.D. tube have to be?

b) Is 8 degrees an accurate measurement?

c) What flange diameter would you like?
 

plowin

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Bill, you can talk to Ken Flower he had mine made. You could have the stainless left raw after completion and have the guy next to brother Wilsons shop polish it. He does a super job,his name is Dan.
 

plowin

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Or have keelboater do it, he sounds interested!
 

BillD

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Figured you'd go to 6" for all that power.

petrel,

The 370 ordinarily requires a 6" exhaust to get ALL the ponies out of it.
But remember, I'm running the 370 "detuned"...maybe running hard cruise getting 220-250 solid cruise hp out of the engine. 5" exhaust will be fine.
I could have gone 6 inches but that would mean raising the deck, cockpit sides etc.etc.etc.ect

I made the 2" water outlets for the stern of my Bertram out of stainless. (It has a side outlet for the exhaust gasses with only water outlets at the transom) The pipe is horizontal to the water line, and the flange was fit up against the transom and tacked in place for correct angle. Then removed for TIG welding and polishing. Not nearly as bad as it sounds. Looks great. The pic isn't that good because I cropped a shot from far away. But it gets the point across.

Looks great!

a) How long does the 5" O.D. tube have to be?

b) Is 8 degrees an accurate measurement?

c) What flange diameter would you like?

I'm in FL this week.

I'd use the old 3" flange as a "template" on the angle and then use the Buck Aloquin measurements for a 5" "straight" flange.
 

petrel

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Figured as much; just couldn't help it. I've got 5" on my 315.
 

Keelboater

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Bill D - Let me get over to the shop this weekend and see what I have for material. I think I may have just what you need. Will send a PM with details. You better bring back some warm, sunny weather with you!
 

petrel

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I bet you don't have a muffler either.
 
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