86 Mercruiser 140 HP (181 cid) exhaust shutter replacement question

[1987sylvanoffshore]

Is the shutter in the lower exhaust manifold? Can this be replaced without taking off the upper exhaust elbow? I looked it up on the mercruiser manual #10 but it is still unclear to me.

 

[wrench 3]

It's in the top of the lower exhaust pipe. The book says that you can get the upper exhaust pipe out without removing the elbow but with the limited access in most boats it's not possible to get enough pull on the hoses.

 

[Bt Doctur]

page 6C-4 the right side shows the lower rubber coupling. loosen the clamps and try sliding it downward to clear the pipe, might be enough room there to wiggle the old one out and install the new one. If not, remove the riser, the intermediate pipe and change it that way.