Exhaust bellow/boot Part Number 70981A3

[sheltonchris1]

I'm a little confused after looking through some of the post about bellows and boots. I referenced the manual for my motor which is a 1986 Mercruiser 5.7L V-8 manual 9 page 7D-2. The part I'm having trouble understanding is the exhaust bellow. Does water run through this piece or not? Mine has a small slit in it and when we were running with it yesterday water was spraying through the slit. We recently took the outdrive off and the engine out to change the lower shift cable and some other maintenance stuff. We checked over the bellows and the gimbal bearing and everything looked good. The main thing I am trying to figure out is if I can change this part without taking the whole assembly apart again. I will wait for responses.

 

[legoman67]

Re: Exhaust bellow/boot Part Number 70981A3

yes water does run through it(mixed wet exhaust), you should be able to replace it with only removing the leg. engine can stay put.

 

[Don S]

Re: Exhaust bellow/boot Part Number 70981A3

Yes, those bellows attach directly to the exhaust risers which are mounted on the exhaust manifolds. On raw wateer cooled engines, water circulates thru the manifolds and risers and out past those bellows and Y pipe into another bellows on the outside of the boat.
The water exiting the exhaust is what keeps the rubber hoses and bellows from burning.

Remove the risers to replace those hoses/bellows

 

[Don S]

Re: Exhaust bellow/boot Part Number 70981A3

yes water does run through it(mixed wet exhaust), you should be able to replace it with only removing the leg. engine can stay put.

He's not asking about the one on the outside, basically just the adapter hoses inside the boat.

 

[sheltonchris1]

Re: Exhaust bellow/boot Part Number 70981A3

Once I remove the risers and install the new bellows, do I need to order any gaskets or o rings to go back into place?

 

[Bondo]

Re: Exhaust bellow/boot Part Number 70981A3

do I need to order any gaskets or o rings to go back into place?

Ayuh,... You'll need the gaskets for the riser to manifold joint...

Did you check the Flappers the last time,... They sit Just below those bellows...