exhaust bellow off again

liusigou

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May 11, 2015
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541
Last friday my boat had the maxium speed of 33m and yesterday it run very slow only 9m and I found the engine side of exhaust bellow was off and the outdrive side is still good. It seemed I lifted the outdrive too high. How can I adjust the trim limit & sender to make the outdrive not to be lifted too high.

Also can I mount the exhaust bellow without moving the u-joint bellow because it is in good working condition.
 

alldodge

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Don't know what drive your working on other then a Merc type

The trim limit sender is on the port side of the gimbal ring. Loosen the screws and adjust. If the limit was working and now it doesn't most likely it will need to be replaced

The exhaust bellows is not needed other then for sound reduction
With it being torn it can be replaced by removing the drive or just don't worry about it

The other side of the issue could be with the exhaust bellow tearing it might be time to replace all the bellows before the U joint tears.

Do you pull the drive every year to inspect boots, gimbal bearing and change drive lube?
 

liusigou

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May 11, 2015
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I have just resealed the exhaust and u-joint below two week ago. nightmare. Is exhaust bwllow mandatory? Somebody mentioned it us full of water while boat is in the water. my boat is Mercruiser 1989 2.5l 120 hp
 

alldodge

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Exhaust bellow is full of water when sitting and is not necessary or mandatory

The Bravo 3 drives don't use a bellow they use exhaust TUBE
 

Pmt133

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Jan 6, 2022
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I've almost always run the tube. Not running exhaust bellows is the marine equivalent of cutting the muffler off your car. It doesn't hurt a thing but may get louder. The tube is a compromise between the two as some exhaust is still directed out the leg but it's so freaking easy to install. The V engines are fairly quiet with or without one. The 3.0l I had, everyone nearby knew you were using a tube instead of the bellows.
 

liusigou

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May 11, 2015
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541
But I do not know why my boat slow down after the exhaust bellow came off. Is it possible that broken bellow has changed the water flow direction and lead to the slow down of the boar?
 
Last edited:

alldodge

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The exhaust bellow should play no effect on how the boat runs. Check inside the exhaust tube coming from the motor to see if something is clogging the exhaust
 
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