building a muffler need help

[sealer]

i have a 5.9L 210 hp cummins marine diesel.iwould like to build my own dry exhaust ,currently i have a 4 inch pipe coming from the engine any ideas on this would be greatly appreciated

[TeddyDiver]

Same thing going on here so I'm all ears...
Made a search here some time ago, and there were some recommendations to have a hospital grade muffler http://members.aol.com/catawampus/silencers.htm

[bilgeboy]

Any reason not to put a riser on the exhaust, then build a wet exhaust system out the stern? There are some nice advantages to this system.

Mike

[sealer]

this boat is used for a fishing boat so theres not alot of room in the bilge for wet exhaust

[TollyWally]

Obviously, a flex connector to deal with vibration and thermal expansion, good thermal blanketing, and planning for future service and maintenence.

Several of the boats I fished on relied on a concept the locals called jetted exhaust. The inner pipe and muffler penetrates the deck and is encased in the outer stack. The stack has fairly large clearences for most of it's length. The inner pipe is centered by various spring or rubber mounted brackets to isolate vibration. The stack necks down the last couple feet to much closer spacing. The inner exhaust is cut off just below or behind the edge of the outer stack. The idea is the exhaust flow attaches to the airstream inside the stack and pulls the air through the stack and cools it. Some guys put louvers or vents at the bottom of the stack, others prefer to pull air out of the engine room to help cool it and increase the fresh air for the engine.

[TeddyDiver]

Originally Posted by bilgeboy

Any reason not to put a riser on the exhaust, then build a wet exhaust system out the stern? There are some nice advantages to this system.

Cold climate (meaning freezing temps about 1/2 of the year) is my reason for the dry exhaust and keel cooling..

[bntii]

http://www.mandrelbendingsolutions.c...let/StoreFront

They were great. Paul will give you 110% of effort to get your exhaust built and this cost is 1/10 of the marine suppliers.

[FAST FRED]

If you a want QUIET! exhaust , Google the "Hospital service" style muffler systems .

Your engine will get a flex hose to allow it to dance on the mounts , then solid exhaust pipe all the way up.

Either a std. pair (in series) of truck mufflers , or the Hospital silencer will quiet the noise.

The hospital units are about 150lbs and not cheap (unless found used at a big gen set shop) .

A rain cap is recommended , partially to keep the rain out , but mostly to keep whichever exhaust valve happens to be open on shutdown from cooling too fast and warping.

We love our Dry stack and keel cooling , far less to break , and far far less danger to the engine.

FF