2 inch exhaust U

[FAST FRED]

A fellow here has an old Wet Snail 32 with a 4-107 Perkins .

He is on a budget and his exhaust finally plugged after 3 decades.

The unit is 2 inch NPT pipe thread in the inlet side (installed straight up from the manifold about 2 ft , makes a U , water is injected with a 1/2 npt fitting , and the now wet exhaust departs in 2 inch exhaust hose.

It looks like a factory piece , but I am unable to find it in any catalog.

If we cant find it two "Street Ells" will be used for the top turn and a simple spray bat (slotted pipe) will be installed in another piece of pipe.

Crude , but not costly.

The fellow would vastly prefer a nice professional made U , if we can find it.

Suggestions? For a source , or nicer home brew?? TIA



FF

[anthony goodson]

Elbows are cheapest ,bends if you've got room ,braze the 316 stainless tube in and they will last 5-6 seasons, foolproof ,and no "marine" price tag.

[gonzo]

A pipe bender will give you a nice professional looking curve.

Siince meeting Tony Athens, Seaboard Marine, there is no longer a need to try and figure it out. Just do exactly as he says. http://sbmar.com/main/articles/desig...xhaust_system/

[FAST FRED]

Great TA article ,as usual!!

We solved the problem with ( 2 inch 2) Street Ells to turn the exhaust gas and an off the shelf $79.00 2in pipe in 2 3/8 out hose cast mixer.OSCO

Looks like it might solve the problem for another 3 decades , but if it fails sooner , $79. isn't that bad.

FF

[bulk-head]

Im sure what is pictured is cheap and might work, but its not optimum.

The water injection is very close to the engine and sea water or vapor could enter the engine .

Also steel and sea water are not friendly. The steel exhaust pipe will age fast due to corrosion and be difficult to de carbonize...

If your installation allows , its Best to keep the steel exhaust pipe dry and insulated, then inject water thru a water jacket, just before the aqua lift muffler.

[anthony goodson]

The system in the picture has been in place on that engine for the last ten years ,the manifolds are 316 stainless and have never needed any attention ,the water injection takes place internally below the joint between the elbows. The elbows were replaced this year for the second time in that time ,at a cost of about £20 ,for both sides. Rather better than the "factory "manifolds fitted to many American V8 petrol engines ,which are a real money earner for the makers ,because they are professionally made very expensive rubbish, that start corroding the day you fit them. If sea water is going to enter this engine it is certainly taking it's time. These fittings are not steel ,they are malleable iron ,and the pipe beyond the rubber is aluminium [dural],and shows no sign of corrosion.

[sbmar.com]

It's hard to tell from the pictures, but if the system is safe from water intrusion and the small dry section is safe , then some credit must be given to the "test of time"...

To me, 15 years says volumes considering I see many a ruined engine that have under
300 hours in factory designed engine/exhaust installs in saiboats every year....

Good job Anthony..

[anthony goodson]

Praise indeed ,many thanks, I have edited the post ,having spoken to my son in law ,that particular engine was ten years ,although that was one of a batch of manifolds I designed and first used 15yrs ago ,so far to my knowledge none have failed. The small dry section is lagged in use ,but stays remarkably cool anyway.