1969 Chris Craft Roamer 46 Refit: Exhaust V

When last I was messing with the exhaust system, I had made the fiberglass outlets that exit the hull near the aft bulkhead in the engine room. Since those will fill up two big holes near the waterline, I need to get them installed and the exhaust systems assembled so we can splash later this year.

The exhaust outlets went off to the paint shop to have the blue stripe applied

Slathered with Sikaflex 291 LOT

Slathered with Sikaflex 291 LOT

Bolted in place, with good squeeze out

Bolted in place

Cleaned up and looking good

Cleaned up and looking good

After installing the outlet on other side, that’s two more holes on the exterior that are filled. But to finish up the exhaust system I need to replace the original Cummins exhaust elbows with something better. The original elbows are listed on the For Sale page for Refit Parts, Tools, Supplies & Leftovers, along with a bunch of other stuff. Two years ago, I checked with several marine exhaust manufacturers about having custom dry exhausts made, with the wet showerhead pointing toward my waterlift mufflers. The estimates that came back were quite high–they averaged $5300 for both sides. So I held off on ordering a set until they were absolutely necessary. Well…we’ve reached that point now.

Next up in our 1969 Chris Craft Roamer 46 Refit: New Exhaust Risers

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6 comments on “1969 Chris Craft Roamer 46 Refit: Exhaust V

  1. William B. Kelleher says:

    I am confused, your picture show what I know as wet exhaust but then you say you are buying dry exhaust.

    Please explain

    Bill Kelleher

    • 1969roamer46 says:

      Hi Bill.
      The OEM Cummins riser is a flange that bolts to the turbo that immediately transitions into a 90° wet elbow. When it fails (and they all do eventually) raw water drains into the turbo, then into the engine, and then you’re looking at a very expensive mess. A “dry exhaust…with the wet showerhead pointing toward my waterlift mufflers” is dry (and insulated) from the turbo up to the top of the ER, at which point it turns (still dry) down and toward the muffler. The wet showerhead is on the down-side of the turn, so if/when it fails, gravity will pull the water into the muffler rather than over the hump and back into the turbo and muffler.
      Here’s a good article describing the concept: http://www.sbmar.com/articles/everything-you-need-to-know-about-marine-exhaust-systems/

      • William B. Kelleher says:

        Believe it or not, I have the same exhaust on my Bertram.
        I just always called it a wet exhaust.

        To me a dry exhaust is dry from the turbo on out.

        Bill Kelleher

        • 1969roamer46 says:

          I suppose it comes down to semantics. From my perspective it’s dry until it it’s wet, but a wet-jacketed system can suddenly and catastrophically go from dry to wet (in the wrong direction), where a dry system that transitions to wet in a fail-safe way is a sort of hybrid.

  2. Doug says:

    Looking really good! Will you need “critter grates”, used to keep muskrats, etc. out of the pipes?

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