Exhaust Rister Hose Question

[probablecause]

A couple of questions. Looking at the first drawing, The inner snout measures 3" across. On the top and the bottom, there appears to be water openings/outlets (purple arrows). My question is, if I hook up a 3" hose and run it up to the polished rim, the water is going to squirt out of the sides. Logic would tell me that I have to use a 4" hose and run it all the way up over the 4" polished part.
The second pic is of the metal gasket that goes between the riser and the manifold. Is there supposed to be another gasket that pancakes the metal gasket? Thanks, Brendan
http://www.***boat.com/image_center/.../Exhaust01.jpg
http://www.***boat.com/image_center/.../Exhaust02.jpg

[dumbandyoung]

Run the hoses all the way up. Use 4" hose with 4" stainless steel hose 2 clamps per riser. So that means you will need a total of 8. The other 4 will be for fastening to the exhaust tips. (2 on each end of hose)
those plates are water block off plates.(Notice how they block the water inlets in the casting) you would use those for a jet boat application. If you use them ....You will need to buy 3/4 inch brass plugs to block off the water inlet on the back of the riser. Also there should be a gasket on both sides. so you need to buy 4 total. If you dont use the block off plates you will need to buy the gasket that is made for those inlets. Or you can use an IMCO gasket and a razor blade to custom make it, and you will only need 2. Call IMCO, ask for Dave or Freddy they will have every thing you need.
If you need a diagram on how to run the hoses I can post one up for you. let me know.
Good luck!

[Ryan00TJ]

Dumbandyoung is right on.
Your guys's avatar's are awesome!!!

[probablecause]

If you need a diagram on how to run the hoses I can post one up for you. let me know.
Good luck!
Dennis,
Thanks for the perfect info. I do have a jet boat also. Please post the diagram. Also, can I use any exhaust gasket for the headers on the BBC? or do I need a special one for the ones that I have. Thanks, Brendan

[dumbandyoung]

Dennis,
Thanks for the perfect info. I do have a jet boat also. Please post the diagram. Also, can I use any exhaust gasket for the headers on the BBC? or do I need a special one for the ones that I have. Thanks, Brendan
The headers should match up to any gasket. By the way what kind of exhaust system are you using? Can you post a picture of the manifold?
here you go, this should help. If you need help understanding the diagram shoot me a pm with your # and and I can talk you through it.
http://www.classicboatbeachbash.com/...ingdiagram.jpg

[Jetaholic]

What's an exhaust rister?

[4trax]

A couple of questions. Looking at the first drawing, The inner snout measures 3" across. On the top and the bottom, there appears to be water openings/outlets (purple arrows). My question is, if I hook up a 3" hose and run it up to the polished rim, the water is going to squirt out of the sides. Logic would tell me that I have to use a 4" hose and run it all the way up over the 4" polished part.
The second pic is of the metal gasket that goes between the riser and the manifold. Is there supposed to be another gasket that pancakes the metal gasket? Thanks, Brendan
http://www.***boat.com/image_center/.../Exhaust01.jpg
http://www.***boat.com/image_center/.../Exhaust02.jpg
I'm running the same thing basically, EMI Thunders. If your running a jet and you want to preheat the water before it enters block to prevent thermal shock to block then you come from the pump to the bottom of your manifold and from there it goes out the top portion of manifold to front of engine and goes in the block and comes out theremostat housing. From thermostat housing to the heat risers and from there out over board along with exhaust. I was not preheating my water but now I'm going to. So I had to replumb my boat for it and get new gaskets like the one you have in your pic. I'm going alittle over board thou. I will be running a gasket then a SS plate I made then a gasket so yes, my SS plate is sandwhiched in between there gaskets just cause after time a year or so they told me to replace gaskets I asked why they said cause the water PSI eats at them and they start to leak:jawdrop: So I asked about my idea and they said I should never have to worry about gasket failure again.
http://i144.photobucket.com/albums/r...s/100_0993.jpg
http://i144.photobucket.com/albums/r...s/100_0991.jpg
http://i144.photobucket.com/albums/r...s/100_0998.jpg
So the plumb job will look like this when I'm done.
http://i144.photobucket.com/albums/r...parts/74_3.jpg