2 inch exhaust U

Discussion in 'Diesel Engines' started by FAST FRED, Dec 15, 2010.

  1. FAST FRED
    Joined: Oct 2002
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    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    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
     
  2. anthony goodson
    Joined: Mar 2007
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    Location: Dorset UK & Murcia Spain

    anthony goodson Senior Member

    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.
     

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  3. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    A pipe bender will give you a nice professional looking curve.
     
  4. mark775

    mark775 Guest

  5. FAST FRED
    Joined: Oct 2002
    Posts: 4,519
    Likes: 109, Points: 63, Legacy Rep: 1009
    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    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
     
  6. bulk-head
    Joined: Dec 2007
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    Location: Antigua

    bulk-head Junior Member

    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.
     

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  7. anthony goodson
    Joined: Mar 2007
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    Location: Dorset UK & Murcia Spain

    anthony goodson Senior Member

    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.
     
  8. sbmar.com
    Joined: Nov 2010
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    Location: S. California

    sbmar.com Junior Member

    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..
     

  9. anthony goodson
    Joined: Mar 2007
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    Location: Dorset UK & Murcia Spain

    anthony goodson Senior Member

    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.
     
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