Big 6" exhaust hose - time to replace

Discussion in 'Diesel Engines/Drives/Transmissions/Props' started by ZZ13, Jan 26, 2016.

  1. ZZ13

    ZZ13 Well-Known Member GOLD Sponsor

    Nov 25, 2009
    Lady's Island, SC
    2001 400 Sedan Bridge
    Cummins 450 Diamond
    The big 6" exhaust hoses have reached end of life on my boat. Time to replace them. Is there a particular manufacturer and/or construction type I should make sure to buy? They are about 1/4" thick (outside diameter is 6.5") and seem to have a metal mesh imbedded in them. I figure I'll just cut off the old ones. They are hard as concrete now after 14 years.
     
  2. cwiert

    cwiert Active Member

    525
    May 7, 2008
    Westbrook, CT
    1998 400 Sedan Bridge
    CAT 3116 - 350HP
    I'm just curious as to why they need to be replaced. Are you concerned they may crack, or are you already seeing signs of cracking?
     
  3. ZZ13

    ZZ13 Well-Known Member GOLD Sponsor

    Nov 25, 2009
    Lady's Island, SC
    2001 400 Sedan Bridge
    Cummins 450 Diamond
    One has a quarter sized bubble where the mesh seems to have disintegrated. Another has a spider crack on the surface of it and also salt will cake on the outside of that same hose where a seam is, after a long days ride. So I figure seawater is weeping through the seam.
     
  4. cwiert

    cwiert Active Member

    525
    May 7, 2008
    Westbrook, CT
    1998 400 Sedan Bridge
    CAT 3116 - 350HP
    Gotcha. How about calling Sea Ray and asking what type they use on the newer boats? Just an idea.
     
  5. ttmott

    ttmott Well-Known Member

    Apr 3, 2012
    Space Coast Florida
    2006 52 Sedan Bridge
    Cummins QSM11
    Spec SAE J2006 Type I unless you are talking about silicone bellows....
    Both Shields and Trident make top hoses.
    If you are getting blisters then there may be some hot spots. Need to make sure the exhaust riser "shower" holes are all clear; sometimes they can get a bit plugged up.
     
  6. ZZ13

    ZZ13 Well-Known Member GOLD Sponsor

    Nov 25, 2009
    Lady's Island, SC
    2001 400 Sedan Bridge
    Cummins 450 Diamond
    By exhaust riser, do you mean the mixing elbow? I have Cummins and there is an elbow bolted to the turbo. Sea water comes in the top and mixes with the exhaust there
     
  7. ttmott

    ttmott Well-Known Member

    Apr 3, 2012
    Space Coast Florida
    2006 52 Sedan Bridge
    Cummins QSM11
    Yes exactly. That ring of holes. Pull the hose off and they should be right there.
     
  8. ZZ13

    ZZ13 Well-Known Member GOLD Sponsor

    Nov 25, 2009
    Lady's Island, SC
    2001 400 Sedan Bridge
    Cummins 450 Diamond
    Roger that. Pulling this hose off looks like it could be a Herculean effort. I take it I don't need to worry about the waterline? That the horizontal hose further downstream is above the waterline?
     
  9. my3sons

    my3sons Well-Known Member SILVER Sponsor

    Feb 24, 2009
    Upstate NY (lake Erie)
    2004 400DB, Onan 9 kw Gen, Highfield RIB,
    Cummins 6CTA
    Bill, yes the top of the hose coming off the muffler is above the water line, and actually so is the mixer, but not by much. I have had mine off before, no problems. If your blister is on the top about 4” back from the mixer, it could be because it gets too hot there when displacement speed cruising. My exhaust hoses get very hot there when running at easy displacement speed, around 950 rpm. After experimenting with the IR gun, I am now trying to keep the rpms up around 1050-1100 when slow cruising for long distances because the extra water that the sea water pump puts out at that speed is enough to fill the shower head and water comes out the top holes of the mixer, cooling the top of the hose better. I have the original hoses on the boat, but if I replace them, I might look at the blue silicone hoses, they are good for about 100 degrees more heat than the black wet exhaust hose.
     
  10. ZZ13

    ZZ13 Well-Known Member GOLD Sponsor

    Nov 25, 2009
    Lady's Island, SC
    2001 400 Sedan Bridge
    Cummins 450 Diamond
    Thanks Mark. The blister is actually on top of the second short hose just past the stainless steel elbow on the port engine. However, I have been doing a lot more slow running. I used to go on plane whenever I could. But starting this past summer we now just take our time most of the time. Usually I stick it right on 950-1000rpm. Sounds like I need to revisit that.
     
    Last edited: Jan 26, 2016
  11. my3sons

    my3sons Well-Known Member SILVER Sponsor

    Feb 24, 2009
    Upstate NY (lake Erie)
    2004 400DB, Onan 9 kw Gen, Highfield RIB,
    Cummins 6CTA
    If it’s the second hose on the port engine then it’s not from what I described, but at least that one comes off a little easier than the starboard side. Start that side by loosening all the clamps and working the hose toward the muffler, then work the stainless elbow off the other end. Good luck.
     
  12. ZZ13

    ZZ13 Well-Known Member GOLD Sponsor

    Nov 25, 2009
    Lady's Island, SC
    2001 400 Sedan Bridge
    Cummins 450 Diamond
    Thanks. They both gotta go. The one between the mixer and the ss elbow and the one with the blister after the ss elbow. Right now I have the blister hose wrapped with HVAC foil tape to flatten and hold the blister. Ha! Don't tell anyone. The purists on here will grill me for that.
     
    Last edited: Jan 26, 2016
  13. ZZ13

    ZZ13 Well-Known Member GOLD Sponsor

    Nov 25, 2009
    Lady's Island, SC
    2001 400 Sedan Bridge
    Cummins 450 Diamond
    I finally replaced these two hoses today. It was very easy. The factory hoses had no wire cool so they just cut right off. They were in terrible shape. About to self destruct. I went with the blue hoses.
    [​IMG]
     
    FeLizDream likes this.
  14. N3716E

    N3716E New Member

    44
    Mar 24, 2013
    Indianapolis, IN
    390 Motor Yacht
    Cummins 480CE
    Looks very nicely done. Where did you end up getting the hose material from?
     
  15. ZZ13

    ZZ13 Well-Known Member GOLD Sponsor

    Nov 25, 2009
    Lady's Island, SC
    2001 400 Sedan Bridge
    Cummins 450 Diamond
    It was an extremely easy job. The old hoses did not have a wire wrap so I just cut them off. I bought the hoses online. Found a place selling a 3' length of the 6" Trident Blue for $235. Unfortunately the other engine needs a 11" piece and my leftover was only 8". Darn it.
     
  16. PMC

    PMC Well-Known Member

    Apr 10, 2009
    Long Island, NY
    2001 40 Sedan Bridge
    Cummins 6CTA
    Looks good. Do you have a bonding wire for that elbow?
     
  17. ZZ13

    ZZ13 Well-Known Member GOLD Sponsor

    Nov 25, 2009
    Lady's Island, SC
    2001 400 Sedan Bridge
    Cummins 450 Diamond
    I do. Its directly connected to the port transmission. I had not reconnected it yet when I took the picture. Thanks for the reminder, though. I actually had forgotten to reconnect it until I looked at the picture and realized it was still off.
     
  18. PMC

    PMC Well-Known Member

    Apr 10, 2009
    Long Island, NY
    2001 40 Sedan Bridge
    Cummins 6CTA
  19. ZZ13

    ZZ13 Well-Known Member GOLD Sponsor

    Nov 25, 2009
    Lady's Island, SC
    2001 400 Sedan Bridge
    Cummins 450 Diamond
  20. FeLizDream

    FeLizDream Member GOLD Sponsor

    240
    Jun 28, 2015
    Marco Island Yacht Club, FL
    2001 Sea Ray 400 Sedan Bridge, with engine synchronizer.
    Cummins 6cta 450 HP, prop 22 Lx 23" L cup.
    Hi Bill, nice job, I’d like to do the same.
    1)- How did you cut the silicone hoses?
    Or you order it already pre-cut?
    2)- where did you order it, remember?

    Thank you
    Fernando
     

Share This Page

Show Sidebar