Exhaust bellows ripped

[Jakem]

I have an mc-1 outdrive and I changed the boots when I bought the boat. I used oem parts and I got back from lake today and was strapping boat down and saw the exhaust bellows ripped open. No idea why...what is the common problem or is there one...it's definitely not age. And it's definitely not heat and melted. It's never got hot or engine overheated. Any ideas

 

[Jakem]

Here's a picture

 

[ScottinAZ]

could have been sitting on a shelf for ages before it got to you. My aftermarket bellows I put on last year are already showing signs of checking, so will be watched like a hawk, and replaced if they get any worse. The exhaust IIRC isnt as critical as the u-joint bellows as the y-pipe goes well above water level and is "open" on the end for exhaust to exit. What is the condition of the other bellows?

 

[Scott06]

Would also think these were sitting on the shelf before you got them or they got nicked installing them with the bellows expander tool.
no issue using it with torn exhaust bellows as the exhaust is full of water at rest anyways.

 

[Jakem]

I will definitely be checking the others

 

[dubs283]

If the exhaust bellows came with a transom reseal kit, i.e. u joint, exhaust, shift cable bellows and w/p hose, maybe assorted gaskets/o rings I'd be suspect of age

Otherwise, most areas I've been acquainted to have used always oem individual parts for transom reseal, of which are readily available most times manufactured within the last year and of reliable quality, ymmv

 

[Jakem]

It was a complete kit

 

[dubs283]

It was a complete kit

Old skool

 

[Jakem]

Would also think these were sitting on the shelf before you got them or they got nicked installing them with the bellows expander tool.
no issue using it with torn exhaust bellows as the exhaust is full of water at rest anyways.

So you can run boat with out it. Sounds sketchy to me lol

 

[ScottinAZ]

there is another option to the bellows, Mercrusiers can also use a two piece tube in place of the bellows. There is a discussion here

Mercruiser exhaust: tube vs bellows

I'm running a 5.7 L EFI engine on an Alpha 1 outdrive. What are the pros/ cons to using an exhaust tube vs the bellows?

forums.iboats.com

being a two piece, it doesnt fully seal all exhaust gases going through it, but allows some to escape for less backpressure (shallower depth and shorter path) on higher horsepower engines. Ill probably install one on mine next time I do bellows, as bellows are a bit of a PITA to get seated, and the exhaust bellows gets quite a bit of stretch in it.

Yours being split is really no different than having a tube in place. It will leak some exhaust gases early, so you may be a bit louder, but its certainly not going to hurt anything at the moment.

My exhaust bellows came also as part of a set, and is pretty badly checked in the volutes of the rubber. If it goes, no biggie, but I am keeping a hawkeye on the u-joint bellows. If that one goes, the boat floods....... and Ill be changing that one out next off season before next years season regardless, at that point it will be 2 years old (one year used).

 

[Jakem]

I've checked over my others and there in great shape. I've pulled off the broken one so no fishing until I change it

 

[Jakem]

there is another option to the bellows, Mercrusiers can also use a two piece tube in place of the bellows. There is a discussion here

Mercruiser exhaust: tube vs bellows

I'm running a 5.7 L EFI engine on an Alpha 1 outdrive. What are the pros/ cons to using an exhaust tube vs the bellows?

forums.iboats.com

being a two piece, it doesnt fully seal all exhaust gases going through it, but allows some to escape for less backpressure (shallower depth and shorter path) on higher horsepower engines. Ill probably install one on mine next time I do bellows, as bellows are a bit of a PITA to get seated, and the exhaust bellows gets quite a bit of stretch in it.

Yours being split is really no different than having a tube in place. It will leak some exhaust gases early, so you may be a bit louder, but its certainly not going to hurt anything at the moment.

My exhaust bellows came also as part of a set, and is pretty badly checked in the volutes of the rubber. If it goes, no biggie, but I am keeping a hawkeye on the u-joint bellows. If that one goes, the boat floods....... and Ill be changing that one out next off season before next years season regardless, at that point it will be 2 years old (one year used).

Is this the tube we are talking about

 

[ScottinAZ]

Is this the tube we are talking about

i do believe it is. biggest benefit is you shouldnt have to pull the drive to install it

 

[dave8311]

I run one of those, no exhaust bellows at all.

I think MerCruiser stopped using exhaust bellow some time ago.

 

[Scott06]

So you can run boat with out it. Sounds sketchy to me lol

Absolutely no issue , exhaust is open at propeller hub so exhaust cavity is full of water at rest. Merc makes an exhaust tube that is connected on one end only. This was first done for bigger engines to lower back pressure but a lot of people use them because they are a heck of a lot easier to install than the full bellows.

my exhaust bellows ripped three seasons ago, ran it for two more years before did the full transom kit with all three bellows

 

[Jakem]

Right o...I am going with the tube.

 

[dubs283]

Tube is designed for a bravo model. Specifically a sbc with bravo 3.

If you install a tube instead of bellows your exhaust will be noticeably louder at idle/low rpm and will soot your transom

 

[nola mike]

Tube is designed for a bravo model. Specifically a sbc with bravo 3.

If you install a tube instead of bellows your exhaust will be noticeably louder at idle/low rpm and will soot your transom

I've been running one for years. I didn't notice any increase in noise (certainly not at idle), for sure no soot anywhere.

 

[dave8311]

I've been running one for years. I didn't notice any increase in noise (certainly not at idle), for sure no soot anywhere.

Same here, not louder and no soot. 305 v8 Alpha gen 2