At this point I'm being told these manifolds being casted wrong are known about but Mercruiser says they are fine and to run them. The gasket section nearest the valve cover barely touches the cast iron wall as it way over hangs it.

I;m in a pickle and would like some help. These have not been run out of paranoia.
Last pic is old manifold to show how gasket vs manifold should be. The others are both sides new manifolds.
Note: The new risers are casted perfect and line right up with gaskets. Also shows this is not a gasket issue.

how did you buy these as a whole exhaust kit or all separate ?

Pm me all related info and the part numbers for manifold and riser and riser gasket , or if it was the complete kit part number. Also are these all Mercruiser parts or aftermarket ?

where did you buy these ?

Possible you might have a GLM riser gasket ?

All Mercruiser. All new. As a Kit. Still have the 'Merc' boxes' shipping foam and all.

I will PM you all info. Thanks.

No, each came in Merc bag. Also gasket lines up perfect with new riser,and old manifold and riser.

I had one side all installed, and I was 2 seconds away from completely dropping riser on the second when my eye caught this. Bet tons of people have not caught this. Doh !

I'll send PM in AM, I have info on my work computer.

so the other side is off with the position of the riser gasket as well ? Its both sides basically what im asking

Let me know where you bought them in the PM.

forgot show me pics of the riser as well front, the sides and mating surface

so does the gasket line up perfect with the riser ?

Turn riser upside down and lay gasket on it -- if no fit then 180 the riser gasket to see if line up changes and or turn gasket over to see if anything changes

Yes, again, gasket lines up perfect with riser.

I was hoping it was the gasket until I put them on the risers. Crazy huh.

Again, once channel of/to Merc was made aware of this with a previous customer of same vendor and after much time back and forth merc said to run it.

Not cool, and I am going to pursue this further, Not fair to anyone.

I'll send you the e-mail from whom parts where gotten from and the name /etc from the Merc guy.I'm sure the Merc guy is the reg sales rep sort of guy, not someone that can actually do something but lip ****. That's my guess at this time.

When weather brakes (hope fully any day) I'll take pics with riser and gasket but believe me the mating lines up purrrrrrrfectly with each other. Manifold...not so.

We have had snow already and been 15degrees below normal. So low 40;s day and low 20'snight. and wind throughout the day for several weeks.

Here is some where in my state right now, 1hr North or so driving from me:

Took some pics today. New gasket with new riser. Fits perfect.
Merc Bag w/part # for gasket(s)
Merc box's the manifolds came in

The two Riser box's and label's: