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  1. #1

    Default Exhaust Baffle Question


    Found this circular "baffle" loose and rattling inside the exhaust house when removing the lower unit for water pump replacement. part number 3 in this diagram. https://www.marineengine.com/parts/j...xhaust+Housing The legs on this disk were severely bent keeping if from snapping in (my assumption). Quite oily inside this cavity.

    What does this part do? How is it replaced? How will the motor perform if it's missing? Just purchased this motor so have no personal experience of performance other than the word of the seller. Ran it in barrel prior to purchase and started and idled fine. I'm replacing the water pump due to a "weak" pee hole stream.

    Evinrude J15RCNC. diagrams says this part is only used in the 15hp model.

    Thanks for your thoughts.

  2. #2

    Default Re: Exhaust Baffle Question

    Looking around I found this:


    If it seems reusable I would put it back.

  3. #3

    Default Re: Exhaust Baffle Question

    Thanks so much. That's it exactly. Seems like there wasn't a solution found in that thread. Performance will suffer seems to be the result. Logic would say it increases back pressure in the exhaust. The one I have is definitely NOT usable and it also appears that the housing would need to be removed in order to replace it. That requires a powerhead removal doesn't it? I've got an 86 model 9.9 that has the same hole with NO baffle. It's bent up pretty badly but it seems to have had 3 "legs" that snap through the aluminum hole and catch on the other side. I doubt if it stood "prowd" of the inner surface but can't know for sure.

    Anyone else notice this on the 15hp models? I could certainly come up with a way to plug off the hole from the outside that would likely stay in place but wondering if anyone else has encountered this and devised solution?
    Last edited by pilot1950; 03-31-2020 at 06:30 PM.

  4. #4
    Join Date
    Jun 2013
    Duluth Mn

    Default Re: Exhaust Baffle Question

    I think they used it for some15s only. Not sure why. I keep em in place when they are used. Fashion something perhaps to do the same job. Probably not gonna take much creativity.
    Last edited by timguy; 03-31-2020 at 10:44 PM. Reason: Typo

  5. #5

    Default Re: Exhaust Baffle Question

    Found some pictures of the component and condition I'm describing.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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