Exhaust Pipe Length - Ford Lehman - Adams 45 Centre Cockpit

[Aussie Monty]

Greetings fellow Mariners,

I seek thoughts and opinions on what impacts increasing the length of my exhaust pipe - beyond the wet box - of my 80hp Ford Lehman Diesel. My Adams is a 45 masthead cutter, centre cockpit and original (custom built) outlet sits just aft of the helm, off to Port. In very light winds, when motoring one gets a nasty hit of fumes so I want to send it all Aft by extending the tail pipe. Existing exhaust is 80mm diameter - both before and after wet box.

You reckon I will compromise the engine function if I add a metre?...even more?

My gut feeling is no.

Thoughts please.

Cheers

Aussie Monty

[Sailmonkey]

What I would do is add a water separator up high where the exhaust used to exit, drain the water there and then run the rest dry to the transom. Eliminating the water in the extended stream will eliminateost if not all of the added back pressure.


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[shakey doug]

Extending your set up 1metre will not upset things at all if the motor is mounted in the normal position for the design.

[model 10]

I don't think the engine would care much because isn't it the water lift system that deals with getting rid of exhaust?

[Lazza]

I have an Adams 45 with a 80hp Lehman with 80mm exhaust which exits at the transom - no problems!!

[Aussie Monty]

Originally Posted by Lazza

I have an Adams 45 with a 80hp Lehman with 80mm exhaust which exits at the transom - no problems!!

Lazza - so your Adams 45 is centre cockpit, with engine bay directly under sole of cockpit?...and you then run your tail pipe all the way aft?..without issues?

Do you mind if I send you some photos or sketches to confirm that my set-up is like yours?...as I would like to run it all AFT to transom..and seek to confirm that this creates no issues.

The photo attached will indicate my set-up...I hope!

Aussie Monty

[Aussie Monty]

Originally Posted by Sailmonkey

What I would do is add a water separator up high where the exhaust used to exit, drain the water there and then run the rest dry to the transom. Eliminating the water in the extended stream will eliminateost if not all of the added back pressure.


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Thanks Sailmonkey, are you suggesting i divert the water at the original thru-hull position - maybe a smaller thru-hull fitting?...and extend the tail pipe Aft to where I require it? Can you refer to an example of this via a link?...so I understand please?

Aussie Monty

[Aussie Monty]

Thanks Lazza...cannot see an attached photo?...you mean my photo? If yes, the strap being the rear arm of the slip?

Monty

[Lazza]

Mine is a rear cockpit - the centre of the motor is about where the rear strap is in the attached pic.

IMO (FWIW) an extra metre isn't going to make any significant difference to your performance.

[Sailmonkey]

Originally Posted by Aussie Monty

Thanks Sailmonkey, are you suggesting i divert the water at the original thru-hull position - maybe a smaller thru-hull fitting?...and extend the tail pipe Aft to where I require it? Can you refer to an example of this via a link?...so I understand please?



Aussie Monty

Yep, something like this.

http://www.centekindustries.com/gen-sep.html

But if you can get a nice smooth self draining run all the way aft, this may be an overkill.


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[Aussie Monty]

Originally Posted by Sailmonkey

Yep, something like this.

Centek Industries - Products

But if you can get a nice smooth self draining run all the way aft, this may be an overkill.


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Cool..thanks Sailmonkey.

[SeaSon]

The only downside of a longer exhaust is reduced performance. In this case under a 1/10 of a horse. A non issue.

Just be sure to use good design to prevent following seas from coming up the exhaust and into the engine. If questions, just search the internet as the wet muffler and loop guys are glad to demonstrate how to use tiher products.