Exhaust Flapper valve issue.

[rm2508j]

So here is my problem! Running the boat on the trailer I here a tinging noise coming from the back of the boat. I did some investigating around the engine and outdrive and found all is well. I looked up the exh. Port on the gimble housing and found part of the flapper valve metal core rattling around the exh hole. I confirmed my suspicion by pulling the rubber exh coupler and bang no more flapper. Lol. I tried every idea to retrieve the rebellious piece of metal, which is none magnetic lol. I tried shop vac, compressed air all for not. Does anyone have any suggestions on retrieving the piece from down low in the exh short of dismantling the whole thing? Or should I leave it the and assume it will rot away like a fish hook? The boat stays in the water for the season so the give it time to rot idea sounds pretty good right now. Lol. BTW it’s a Mercruiser 3.0 w/ alpha 1 gen 2.

 

[kulle]

I dont think it would harm anything. When I pulled my bell housing off to change ujoint bellows, i had 3/4 of the shutter lodges in the exhaust bellows. I suppose one thing comes to mind. Pull one of the exhaust elbows off and get to the top of the exhaust where the shutter SHOULD be and maybe use a hose and try to flush it? Assuming you have the exhaust bellows connected to the bell housing ? If you had a exhaust tube it would likely come right out with water. Perhaps cut the exhaust bellows from the bell housing side and that would also flush it out with hose or a run on the lake- my .02

 

[rm2508j]

I don’t have exhaust bellows. I have the inline 4 Mercruiser with one exh outlet on the motor which looks like an upside down J with rubber couplings connecting the segments that runs down to the lower portion of the gimble housing. So I think. Lol

 

[rm2508j]

I retract that last statement. I do have exh bellows, my mind was somewhere else.

 

[Bondo]

Does anyone have any suggestions on retrieving the piece from down low in the exh short of dismantling the whole thing? Or should I leave it the and assume it will rot away like a fish hook?

Ayuh,...... Pull the drive, 'n dig it out from below,......

Don't leave it in there, as it can block the exhaust flow, causin' other runability issues,......

 

[altitude 411]

this..https://www.amazon.com/RAM-PRO-Flex...grabber+tool&qid=1558524242&s=gateway&sr=8-25

 

[Scott Danforth]

pull the drive

 

[achris]

Pull the boat out of the water, pull the drive and remove the broken shutter...

Leaving it in there, it will vibrate and quite quickly wear a hole through the exhaust pipe. The next step is a boat on the bottom of the sea/river/ocean/marina... Not a good look... And I'm not being over dramatic, I've personally experienced it...

By the way, leaving it in the water, it won't 'root away', it's stainless... (Hence the magnet does not work)

Chris....

 

[Redtruck12]

Hey just stopping by from the restoration forum
I’m in the process of reassembly after a year of stringers, transom and other fibreglass fun on my Duo Vagabond.
same 3L in-line 4 Mercruiser but it’s a 1974 mc-1 out drive,
i saw that little flapper in my “upside down J” pipe/exhaust elbow and was curious what the heck it is for????
Mine looks intact but seems loose in the pipe (surely doesn’t seal the pipe.
so I guess my questions are;
what does it do / what is it for ?
And
What should I be looking for while inspecting it??

 

[rm2508j]

Well fellas, after numerous attempts and ideas. I got it! A wire hanger with a little hook on the end with my flexible bore scope from amazon (29.99 btw a great tool!) taped to it and the determination of a mental patient. I fished the leftover flapper valve out from the depths of the lower exh down pipe. I thank all for the advice and guidance. This is a great forum with good people! Thank you!

Happy And Safe Boating

 

[rm2508j]

The flapper valve stops water from entering the engine when the boat is sitting in choppy or rough water. It’s a splash guard in a way.

 

[Redtruck12]

Thanks for the explanation.
So what does a good one look like
And more importantly a bad one?

 

[rm2508j]

I just spent 2 nights fishing a broken worn out one from my lower exhaust pipe. If there is any question about it’s condition I would just replace it. Especially after what I went thru to retrieve my broken one out! The end blocks should be snug in the pipe and the valve rubber flexible and in good condition. If your in there already and don’t know how long it’s been in service just replace it. That’s what I would do

 

[wellcraft-classic210]

Redtruck12
Their is a post in the stickies on shutters under mercruiser -- Thanks to Achris