Anyone out here know why Mercruiser superseeded the stainless elbows and went back to the cast elbows with the 4 long clamp bolts running through it? Is there performance differences, water reversion, or was it a cost issue?

Yates

I think it was beacuse of leakage where the riser meets the manifold.

The stainless elbows with the short bolts had sealing problems. The cast riser with the long bolts seems to more evenly distribute the torque and they are less prone to leaking. I don't know why they didn't just start making the cast style elbow out of stainless though.

geee lets think about this one.......as simple as dissimilar metals in a salt water enviorment

My kid has been running a pair on his fish boat two years now, first season he had the block off plates. He pulled it last year put a new pan on and a few other parts and a paint job, he pulled the risers to check the iron. He left the plates out this year and sea cooled the manifolds less for his closed cooling to handle, always sealed them with good old Aviation sealer. Another thing I measured a set I have and the exhaust opening is 3/16" wider across, should give a little more breathing.

Phil

The disimilar thing don't hold water, iron & stainless are in the same family. I was a salt water boat mechanic for a very long time, stainless does very well with other metals.

Phil

I have four (4) of those SS elbows I'd be happy to sell if anyone wnats them !!

Poorsche , you still have those by chance?

I have a set off a 496 for sale.

Chris