exhaust shutter WHY WHAT FOR

Everybody thank you for helping me in the past .Now i would like to know about this exhaust shutter wile my riser is off ( 1991 3.0 cobra) i pulled the rubber off the tube and all I found was a little rod with no holes for screws or rivits does this mean my boat did not come with one this is the first time its been apart since new also what does this do for the boat or motor. THANKS

Re: exhaust shutter WHY WHAT FOR

Alfred jobs said:

Everybody thank you for helping me in the past .Now i would like to know about this exhaust shutter wile my riser is off ( 1991 3.0 cobra) i pulled the rubber off the tube and all I found was a little rod with no holes for screws or rivits does this mean my boat did not come with one this is the first time its been apart since new also what does this do for the boat or motor. THANKS

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Are you saying that your shutter is not there? If it's not there then it fell out. It's most likely stuck in the exhaust outlet. When I pulled my drive off in the fall I found one of my shutters stuck down there.

Now as far as what it does. The exhaust shutter lets the exhaust out but keeps water from getting back in the exhaust and locking up your motor. When you suddenly stop and the water splashes on the back of the boat it tends to try to go back up the exhaust with the shutters the water can't do that.

Re: exhaust shutter WHY WHAT FOR

Volvo bought OMC and then issued a service bulliten that flappers are not necessary. I have a 3.0 OMC that dropped one down the exhaust and caused problems with back pressure at 3000 rpm and up. Cut out, ran crappy. Had to remove the drive to get it out. These are hard to find. A dealer in Tulsa never did come up with one for me. For my part, I think one should be used, like Jrolland said. It's a shame with all the space age stuff, they can't make a better one that won't melt. I guess if your impeller gets shot, then you don't get enough water to keep the exhaust cool at the flapper. There is a bushing on each end of the flapper pin that you might want to replace. Iboats didn't have it. Flapper #3853864, gasket#3850495, bushing#3855517 (need 2). Flapper rod (pin) #3852753. I got Flapper from Marine Parts Express, 877 621 2628. www.marineparts express.com Other parts from marineengine.com

Re: exhaust shutter WHY WHAT FOR

Volvo bought OMC and then issued a service bulliten that flappers are not necessary.

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Ayuh,... Personally,.. I wouldn't run a boat without some sort of shutters to block the water.....
Even Thru-hulls use shutters, flappers...

Re: exhaust shutter WHY WHAT FOR

I ran my 85 4 Winns with thru hulls and no flappers, straight exhaust. Everytime I came off plane I cringed. I wont do that again, they are there for good reason.

Re: exhaust shutter WHY WHAT FOR

Bought mine with missing shutters, too. Asked the dealer for new shutters, pins and bushings. Showed up 2 days later. I must have a special guy behind the parts counter; there's never a problem getting what I need for my Cobra.