1991 OMC Cobra 3.0 exhaust bellow

[BBoettcher]

I have removed the lower leg on my 1991 OMC cobra 3.0 to replace the lower shift cable. When I examined the lower exhaust bellow I am noticing a twisted smooth piece of rubber inside. It appears to be attached. Does any know what this is and if it should be there?

 

[Scott Danforth]

most likely its what is left of your flapper or the inside of the exhaust hose

neither of which live more than 15 years, and less than that if you ever have an over-heat.

check your flapper, and inspect the inside of your exhaust hose

 

[BBoettcher]

[No message]

 

[Scott Danforth]

now go inside the boat, pull the exhaust elbow and the hose, inspect them, and look at your flapper and inspect that

 

[BBoettcher]

Could his be a rubber liner for the cast exhaust? Or could it be a check valve to prevent water from going back through exhaust? I am wondering if it should be pushed back up the cast tube?

 

[Bondo]

Could his be a rubber liner for the cast exhaust? Or could it be a check valve to prevent water from going back through exhaust? I am wondering if it should be pushed back up the cast tube?

Ayuh,..... Welcome Aboard,..... There is no rubber liner, 'n the check-valve is called the shutters, or flapper,.....

Pushin' it back in is not the answer,....
Pull it out, 'n replace it with new, it goes at the top of the down-pipe,.....

 

[BBoettcher]

I don’t believe this is a shutter or flapper. If I were to pull it out it is a piece of rubber that is about 6” wide by at at least 10” long and about 1/8” thick. I do not want to remove if it belongs there. It looks nothing like a shutter or flapper? I can not find any parts on line that would look like this. I am asking if anyone has ever seen this in another OMC and what it may be

 

[PITBoat]

If I were to pull it out...

Yes. It looks like an exhaust restriction to me.

 

[BBoettcher]

I was able to free the piece of rubber and it is 1/8” thick x 6” wide x 12” long. There is heat damage on the end closest to the motor. It looks like it was rolled up and placed in the exhaust bellow. This exhaust bellow is vented on the bottom by OEM design to let water drain out. The boats exhaust makes some noise due to the design and the height of where the leg mounts on this pontoon the vents on the bottom of the exhaust boot ride just above the water line. I am wondering if someone stuffed this in the exhaust boot in an attempt to make it quieter. I am planning to reinstall the leg and leave this piece out as I feel it was restricting the exhaust flow. Does anyone have any other ideas or suggestions.

 

[Bondo]

I am wondering if someone stuffed this in the exhaust boot in an attempt to make it quieter. I am planning to reinstall the leg and leave this piece out as I feel it was restricting the exhaust flow.

Ayuh,..... Yer probably right,..... leave it out, 'n try it,.....

 

[Lou C]

Very odd!