Bellows question please.

Gary H NC

Fleet Admiral
Joined
Dec 1, 2005
Messages
8,972
I just finished replacing the bellows on my Cobra drive.
Why did the old exhaust bellows not have any holes in it and the new ones do?I take it that its for drainage?
Also,will the exhaust be louder?
No mention of it in the service manual...
 

muskrat

Chief Petty Officer
Joined
Apr 13, 2004
Messages
445
Re: Bellows question please.

new style yes you right.
 

Boatin Bob

Lieutenant Commander
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Sep 24, 2001
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1,858
Re: Bellows question please.

Drainage and back pressure relief. Shouldn't be any louder as you normally run with the drive down which compresses the bellows (closes up the slits).
 

WillyBWright

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Dec 29, 2003
Messages
8,200
Re: Bellows question please.

Not so much for drainage as exhaust pressure relief at non-planing speeds. You might notice a little more noise, but not much. When the drive is down, they're not very open. It was an upgrade that began shortly after Cobra's introduction. I believe 87 was the first year for them.
 

Gary H NC

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Dec 1, 2005
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Re: Bellows question please.

Thanks, I wouldn't think that old bellows was original,it was in good shape if it was. just some minor dry rot cracks.Maybe someone replaced it before with the old style..
 

cobra 3.0

Lieutenant Commander
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Jul 31, 2003
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1,797
Re: Bellows question please.

I think yours maybe an aftermarket bellows(GLM or Sierra) like mine. My original OMC one from a few years ago had no ribs/cuts either. This cut version is louder and stinkier at slower speeds. The back end of the boat gets dirtier too. Personally, I much preferred the older one.
 

Gary H NC

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Joined
Dec 1, 2005
Messages
8,972
Re: Bellows question please.

Yep,It was a sierra kit. I may put the old one back on.I was more interested in getting the ujoint bellow changed anyway.
Louder and exhaust smell...yuck:%
 
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