the old riser has a pretty thick area of iron where the fourth water vent from the exhaust mani goes ..... This new riser has a thinner area of iron in that same spot..
the gasket sent with the manifold is a 3 water jacket and the so is the riser all good
---just that this new riser is missing some meat at the foot where it sits over this fourth jacket vent it acts like a stopper... Something is up...what do you guys think
pics might help. just to be sure, are you CERTAIN that it's the correct replacement mani and gasket? i can't quite remember, but on some systems there was a step to pierce the gasket.
Just got off the phone with rocky from mercruiser and he verified that 4 water jacket holed manifold did come with a 3 water jacket gasket. My oem riser has 3 water jacket holes. This equals one side of the foot of the riser acts as a stopper. Kinda lame engineering --im thinking this is cost cutting for a more universal manifold.
