DYI castiron / stainless riser conversion 2006 Baja questions?
 

Hey Everyone! First post here ...

I have a 2006 Baja with a 305 merc 5.0 mpi alpha drive eng code OW35xxxx. It is sea water cooled, single piont drain with thru hall ext.

After 11 years if service I need to replace the ext manifolds and risers. I didnt want stock and needed ti stay around 1300$.

I bought a set from Hardin marine the manifolds are castiron and stainless risers. http://www.hardin-marine.com/p-22473-cast-iron-stainless-steel-exhaust-system-sbc-kit-w-standard-offshore-stainless-risers.aspx

1. I will be using this system as a wet joint system. Will I need to use a water restriction gasket between the riser/manifold joint since there is a water inlet on the riser?

2. Over the winter I will be converting it to a dry joint system by using a stainless block plate between the manifold/riser joint and using a jumper hose between the manifold and riser. The water inlet will be supplied under the manifold. Will this be enough water to cool the manifold and riser?

Has anyone done this before with this kit?

Thanks

anyone?

so you are replacing dry joint merc exhaust with old-style wet joint manifolds and stainless risers? what is wrong with stock? the big shiny risers only add bling. why buy wet joint to convert to dry joint? current set-up is 1 hose to bottom of each manifold? that will work with these.

There are not many options for stainless steel risers and a dry joint system. I couldnt find a direct bolt on that would fit my application, so I am improvising. This is what I plan on doing over the winter https://www.google.com/search?q=sbc+...32yi8nUBpJnsM:

Im sure a stainless riser adds more than just bling.

800 bucks for those 2 risers. 10 hp. You haven't bought these yet? Shop for a used set of mercruiser stainless risers. NLA new, but 75 apiece to 300 a pair on ebay. High quality stainless. Don't rot. Then buy new iron or Aluminum from GLM wet joint manifolds.

i wonder if the big block stainless risers have the same bolt pattern as the small block risers do?

I just shopped for manifolds and was told that GLM no longer makes wet AL mani's.

Hardin still has them listed I believe. I can tell you if you get the castiron GLM manifolds be sure to check the gasket surfaces. I just got mine last week and I had to file down the riser surface because it was not flat. I also repainted them with Epoxy paint. They work and look good now.

I used GLM manifolds and sanded all of their coating off of both gasket surfaces as directed by a buddy who is a career marine mechanic. He's had good experiences with GLM's using this method in the past. I then installed and coated both sides of each gasket with Perfect Seal. FWIW Merc's manifolds already come with the gasket surfaces as bare metal.

I'm quite sure all the people having issues with GLM's sealing are because they leave the dipped material on the gasket surfaces. In my 18 years of playing with cars, bikes, boats etc I've NEVER seen a sealing surface that hasn't been bare metal, so I have no idea what people are even thinking of by installing them coated.

Keith

http://i1000.photobucket.com/albums/...ull%20view.jpg

finished product, looks and sounds great! Softwall exhaust tubing has a slight angle. No burning rubber noted after running the crap outta it in the ICW.