1974 140 Exhaust Flapper

[bbook83]

After re-installing the engine, but before installing the exhaust riser and rubber tube, I had second thoughts about my earlier decision not to replace the exhaust shutters. Although I know it would have been much easier to replace the shutters before installing the engine, I figured that the job was designed to be done with the engine in place anyway. As I look at the Mercruiser part # 45586 exhaust shutter, it appears as though the brackets that support the hinge of the shutters (which are riveted to the exhaust pipe) must come out to install the shutter. Am I correct on that? If so, it is going to be a problem because there isn't room in my application to drill out the rivets. I see a NLA Mercruiser part # 46017A-1 available on ebay and other places that is an exhaust shutter kit that appears to fit inline in the rubber tube between the exhaust pipe and the riser. Does anyone have experience with using that approach?

 

[Alumarine]

Sorry, can't offer an opinion on that part.

But, you don't have to drill it out.

You can use a dremel or grinder to grind off the rivets on one of the 2 clips that hold the flapper in. That allows you to remove the old flapper.

You can use the clip that's left there with one of the new clips.
It makes sense once you remove the flapper.

Then use stainless 10-32 machine screws to attach the new one.

• IMG_0027 (450 x 600).jpg (107.5 KB, 1 view)

 

[bbook83]

Great solution, Marc. I'll give it a try and report back.

 

[bbook83]

No Title

I ground the rivets off one bracket and installed an OEM exhaust shutter just as Marc had suggested. I had to trim the rubber where it first made contact with the brackets, to get it closing to the point shown in the picture. It certainly isn't water tight, but would stop a whole lot more water than what I had before, as the shutter was completely gone. As I have never seen one of these in place, can anyone tell me if this looks about right?

 

[Alumarine]

Pictures pretty small but it sure looks fine.
And you're right it doesn't have to be water tight.
Well done.

 

[bbook83]

Thanks, Marc. I'm not sure why I can't upload pictures that can be expanded for a better view. Now on to bolting up the exhaust elbow to the manifold. Did you use any sealant on that gasket on your project?