Coolant Conundrum/Exhaust Riser Replacement [Master Thread]
- Thread starter Prairie Schooner
- Start date
Prairie Schooner
Jeff & Donna, E35-3 purchased 7/21
EXHAUST RISER / MIXER INSTALLATION - pt 1
The riser assembly is installed and working, though I'm going to revise the brace.
There were a couple ways the different fittings could have been arranged, but this worked well with the way I was going to add the auxiliary support/brace. The mixing head was cleaned with Barnacle Buster, primed with engine primer, and painted with engine paint. The manifold flange was abrasive cleaned and sprayed with engine grade primer and paint. (I don't like the Universal gold color so anything I take off has been getting a new paint job. But to be honest, the gold is a pretty good color because it shows oil and other stains well, making it easier to trace problems.)
It was Doug's @bigd14 suggestion in post #125, page 7, that got me here. Thanks Doug! Because of the height of our riser, it couldn't go direct from U-bolt to manifold as in his sketch. Once I got the idea of using turnbuckles, I was enamored of the way it would look and couldn't break away from it. A number of prototypes for the manifold attachment were made, during which I re-imagined the U-bolt orientation. I used aluminum flashing, then .060" aluminum for the prototypes.
The final piece would have been a perfect candidate for water jet cutting, but I needed to turn it around fast. The .125" stainless steel was drilled then cut out with a jewelers saw. From layout to finished piece took about four and a half hours. It still bothers me that I didn't line the jaws of my vise when I bent the 'wings'.
The riser assembly is installed and working, though I'm going to revise the brace.
There were a couple ways the different fittings could have been arranged, but this worked well with the way I was going to add the auxiliary support/brace. The mixing head was cleaned with Barnacle Buster, primed with engine primer, and painted with engine paint. The manifold flange was abrasive cleaned and sprayed with engine grade primer and paint. (I don't like the Universal gold color so anything I take off has been getting a new paint job. But to be honest, the gold is a pretty good color because it shows oil and other stains well, making it easier to trace problems.)
It was Doug's @bigd14 suggestion in post #125, page 7, that got me here. Thanks Doug! Because of the height of our riser, it couldn't go direct from U-bolt to manifold as in his sketch. Once I got the idea of using turnbuckles, I was enamored of the way it would look and couldn't break away from it. A number of prototypes for the manifold attachment were made, during which I re-imagined the U-bolt orientation. I used aluminum flashing, then .060" aluminum for the prototypes.
The final piece would have been a perfect candidate for water jet cutting, but I needed to turn it around fast. The .125" stainless steel was drilled then cut out with a jewelers saw. From layout to finished piece took about four and a half hours. It still bothers me that I didn't line the jaws of my vise when I bent the 'wings'.
Last edited:
Prairie Schooner
Jeff & Donna, E35-3 purchased 7/21
EXHAUST RISER / MIXER INSTALLATION - pt 2
The manifold flange studs weren't long enough to accommodate the additional stainless plate so I ordered longer ones. A high temperature anti-seize product was used for assembling all this, including the stainless & iron riser. Almost everything I put back together on the boat gets some kind of anti-seize product.
Those were the shortest stainless turnbuckles I could find that had clevis pin ends and still looked strong enough. To get them past the riser to the eye nuts I went with a bigger diameter U-bolt and added silicone padding. There are a couple problems with this. 1) It is all too squishy. 2) I angled the mixer about 20º toward boat center to be more in-line with the muffler. The inboard turnbuckle is tightened about as much as it can be. This will eventually be replaced with a smaller U-bolt and a fabricated piece something like this in place of the U-bolt plate.
This is certainly more complex and maybe more robust than anybody needs. But I spent my career in product design and development (prototypes and tooling models) and this is kind of my default setting. Change is hard.
- - - - -
Seaboard Marine had some great examples of exhaust installations. None of their specific examples made it to our final configuration, but they helped expand my approach.
- https://www.sbmar.com/articles/proper-exhaust-bracing/
- https://www.sbmar.com/articles/custom-marine-wrap-around-exhaust-supports/
- https://www.sbmar.com/articles/custom-marine-exhaust-supports/
The manifold flange studs weren't long enough to accommodate the additional stainless plate so I ordered longer ones. A high temperature anti-seize product was used for assembling all this, including the stainless & iron riser. Almost everything I put back together on the boat gets some kind of anti-seize product.
Those were the shortest stainless turnbuckles I could find that had clevis pin ends and still looked strong enough. To get them past the riser to the eye nuts I went with a bigger diameter U-bolt and added silicone padding. There are a couple problems with this. 1) It is all too squishy. 2) I angled the mixer about 20º toward boat center to be more in-line with the muffler. The inboard turnbuckle is tightened about as much as it can be. This will eventually be replaced with a smaller U-bolt and a fabricated piece something like this in place of the U-bolt plate.
This is certainly more complex and maybe more robust than anybody needs. But I spent my career in product design and development (prototypes and tooling models) and this is kind of my default setting. Change is hard.
- - - - -
Seaboard Marine had some great examples of exhaust installations. None of their specific examples made it to our final configuration, but they helped expand my approach.
- https://www.sbmar.com/articles/proper-exhaust-bracing/
- https://www.sbmar.com/articles/custom-marine-wrap-around-exhaust-supports/
- https://www.sbmar.com/articles/custom-marine-exhaust-supports/
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Prairie Schooner
Jeff & Donna, E35-3 purchased 7/21
Bravo! A good radio is a beautiful thing.Big deal, Jeff. I installed a new VHF radio this weekend.That’s some fine work man. Quite a detailed project. Well done.
Thanks, Brian. And it hasn't fallen off yet.