I asked this question under the Baja section w/ no one responding/knowing???
2002 25' outlaw 800hrs 6.2/377 engine---I just replaced the manifolds and risers,,,,,whew alot of work..I have been hearing of a new after market dry joint riser being built..Instead of the water flowing through the rectangular opening from riser to manifold, the water goes through a round hole/pipe section and the rectangular openings are blocked off. Does anyone know of this??? Will I be able to open the 2 round pipe plugs in the manifolds and place the new risers and water o rings onto the manifold and have a dry joint exhaust system ????
Thanks-----Mike Tampa Bay

the dry joint exhaust has been out for a few years..you wont be able to use the risers on your manifolds tho..all they did was move the water ports further away from the exhaust ports and combined all the small ports into two ports..either go with performance exhaust or stick with what you have because the dry joint riser gaskets are pricey,like 50 bucks each..

look at the pics of the dry joint on google ..
http://www.google.com/search?rlz=1T4...w=1259&bih=683

Mr fixxall----thanks----I see that the new risers have moved the water passages out further and made them round----on my Merc manifolds, I have 2 round passages with threaded plumbing plugs that seem to line up with the new water passages on the new dry risers........I thought I could un-plug the plugs, put the new risers and gaskets on, with the red o-rings and be good to go without changing the manifolds!!!!??????
Thanks-------Mike Tampa Bay

You would have to find some way to plug the current rectangular openings in your manifolds, or you would still possibly have the same leakage issue. If they had made them out of aluminum, it would be a simple matter of getting a welding shop to weld them up for you, and then drilling and tapping for fittings and running the external hoses to the risers like the aftermarket exhaust companies do. The Merc 496 engines (8.1) use an external jumper hose and dry joint, and they are supposed to be the same flange pattern as the Mk IV/Gen V/VI big blocks, but this won't help you with your small block application.

I believe they make a blockoff kit for routing the water external of the joint. Its 2 gaskets and one stamped sheet metal part that gets sandwiched betweent the gasktes. I have them on my full closed cooling carver where the manifolds run green antifreeze. I'm not sure you will be able to get the plugs out of the risers and manifolds though. I tried before and gave up.

Here you go.....

http://bpi.ebasicpower.com/c/MER9C/G...for+Mercruiser

Thanks guys, I thought the new gasket set would close off the rectangular passages from there photo's------I guess the real question now is---IF I can get the plugs out/off my stock merc manifold, which by the way is brand new, will the dry joint risers and gasket sets bolt up to my brand new stock Merc manifolds???????? Hopefully someone who sells they will read this and answer!!!!
Mike---Tampa Bay!!!!!

Thanks Blue Thunder-----I will call them and get my answers----------Thanks !!!!!!