MC-1 GM Inline 6 250 Ci Exhaust shutter question

[998cc]

My exhaust shutters were missing, so I have never seen how they are installed. There is a bracket in the exhaust tube with a bar that goes across the top of the opening; this bar is a little loose. Is this bar that remaining piece from the old shutters? Otherwise, I have no clue how these go in.

Russ

 

[achris]

Yes.

 

[998cc]

This may sound like a silly question, Chris. How does that bar come out, and how do the shutters go back in? It seems that the bracket would allow removal, but no dice so far. I don't want to apply too much pressure for fear of cracking the cast iron exhaust tube/elbow.

 

[achris]

Mercruiser service manual 3, section 5C, page 5 has the procedure. Do you have a manual? (it involves cutting/grinding the rivets off one side of the support member of the old shutter)

 

[998cc]

Wow..grinding out rivets to replace a consumable rubbe part is right up there with spec'ing stainless steel nails in the gimbal pins!! :facepalm: :faint2: I have original manuals I and II...but not III. What type of rivets will suffice for replacement? Pop-rivets come to mind, but they are aluminum and not OEM material. I guess a shortened smooth-shank screw, heated and peened would work as well.

Last shutter question: Smooth side up or down??


BTW, I have only seen the world from about 72 feet below at this point. Planning to do 100' in May at Carmel, California.

Russ

 

[Alumarine]

I used a 8-32 or 10-32 SS machine screw. You could run a file on the exposed threads if you were afraid the nut backing out.

 

[achris]

...BTW, I have only seen the world from about 72 feet below at this point. Planning to do 100' in May at Carmel, California.

Russ

I managed to get down to 13,000 feet a couple of weeks ago, off Bermuda.

Oh, yeah, I was using one of these ->