Exhaust bellows, piece of rubber inside?

[pikiewicz]

I just bought a larson with a 5.7 liter and a gen 2 drive. I took off the drive to replace all the bellows and found a piece of rubber resting on the shifting shaft. The shaft that passes through the exhaust bellow area. It kinda looks like a flap or a piece of a shoe. Kinda half circle shaped but longer. Any ideas?
Pik

 

[Don S]

Re: Exhaust bellows, piece of rubber inside?

Sounds like a broken exhaust shutter (aka flapper) You need to pull the exhaust risers and inspect/replace the flappers.

 

[starsnstripers]

Re: Exhaust bellows, piece of rubber inside?

Sounds like your exhaust flapper from your exhaust Y pipe. they can corrode away and come apart.

 

[Bondo]

Re: Exhaust bellows, piece of rubber inside?

Ayuh,... Or Burnt up when the motor was run,.. Dry...

 

[ENSIGN]

Re: Exhaust bellows, piece of rubber inside?

Sounds like it ran hot and burned up the shutters

 

[ENSIGN]

Re: Exhaust bellows, piece of rubber inside?

Since you got the drive off put a water pump in it GOOD INSURANCE!

 

[achris]

Re: Exhaust bellows, piece of rubber inside?

The early style shutters were little more than an oval disc with a stainless steel shaft through them... With use the shaft wears through, and all the bits end up in the exhaust system somewhere... You got luck in that it fell all the way through and stopped where it couldn't do any harm....

I was not so lucky with my first V6. The shutter fell off (NEVER been run dry!) and lodged in the bottom of the Y pipe. There it sat, vibrating away, and wearing a hole in the bottom of the Y pipe.... When did it punch through? When I was more than 30 nautical miles off the coast, that's when!!! Luckily I noticed the water in the boat before it was too late and the best bilge pump in the world took over. (Two scary decks with a bucket each. ) We had been game fishing and a couple of BIG sharks had zeroed in on the action.

The original shutters have been superseded by a new style shutter which will not longer fail in that manner.

Chris.......

 

[pikiewicz]

Re: Exhaust bellows, piece of rubber inside?

Thanks for the info. I really don't know where the y pipe is and how big of a job is it to put in a new flapper? Any pics or info would be great. Is it a big job? Doe it need replaced?

 

[achris]

Re: Exhaust bellows, piece of rubber inside?

Thanks for the info. I really don't know where the y pipe is and how big of a job is it to put in a new flapper? Any pics or info would be great. Is it a big job? Doe it need replaced?

The Y pipe is so called because it looks like the letter Y.... It's the exhaust pipe, from the end of the exhaust elbow to the bottom of the transom housing.

Replacing them is a reasonably important job, but not difficult. Just remove the elbows, with the rubbers and the short aluminium tube below it and you have easy access to the shutters... at the top o f the Y pipe.

The new style shutters come with all the instruction and parts you need to retrofit the old style Y pipe... The part number for the new shutters is -807166A3 (that gives you a pair)....

Chris........

 

[pikiewicz]

Re: Exhaust bellows, piece of rubber inside?

Thanks. I will take a look today. Are there any other gaskets, etc. I will need to get? Should I be concerned that something else is now wrong? Just bought the boat and found this rubber thingy. Now I am worried. I did run the boat and it came up to 165 fehrenheit and leveled off?

 

[Sean-Nos]

Re: Exhaust bellows, piece of rubber inside?

Here is a pic of what the flaps look like you should have two bits like the heel of a shoe on each side so make you find all 4 and the exhaust is clear.
http://www.iboats.com/Mercruiser-In...8435888--**********.614737362--view_id.270890

 

[pikiewicz]

Re: Exhaust bellows, piece of rubber inside?

Thanks. It looks like the bigger model that is connected to some type of housing. Again, could it be a bigger problem? Do I need to buy anything extra(gaskets?) for this job?

 

[Sean-Nos]

Re: Exhaust bellows, piece of rubber inside?

Thanks. It looks like the bigger model that is connected to some type of housing. Again, could it be a bigger problem? Do I need to buy anything extra(gaskets?) for this job?

As said by ENSIGN have a look at your water pump and change the impeller,you might also have to get a new gasket for your elbow riser they tend to break up when you take them off,They look like this http://www.iboats.com/mall/image/vendor/16/bigger/18-0885_big.jpg

also when ever I take off a stern drive I change all the bellows, gasket,and O rings just to be safe You can get a kit like this depending on what drive you have.
http://www.iboats.com/Transom-Seal-...5068084--**********.230537402--view_id.187684

 

[pikiewicz]

Re: Exhaust bellows, piece of rubber inside?

Ok thanks for all the help. I found the broken flaper. Wow I picked the right side first. Inspected everything and they look great but one flapper is torn off. I took the other side apart and it looks fine. Since I am into this thing, is it best just to replace the flappers/ Is it possible the engine didn't overheat and It just ripped? These flappers still have their nipples on the rubber.

 

[cooter2506]

Re: Exhaust bellows, piece of rubber inside?

Replace both flappers while its apart if one failed other one is due too. Run engine in driveway with muffs and check for overheating. Probably didnt over heat just had worn out flappers.