Exhaust Flappers

FreeBeeTony

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Joined
May 15, 2002
Messages
3,991
I have been hearing a noise towards the rear of my engine. In the past I only heard it sometimes when I first started it or/and at low RPM's intermitently. When I started it last night it was more consistent, still only at idle and at low RPM's (no wake zone speed). As soon as I give it some throttle the noise just about disappears.

I am pretty sure it's the exhaust flappers. Wanted to pull the elbows tonight to check it out but got rained out. Any suggestions/advice on this (hopefully simple) project?
 

Don S

Honorary Moderator Emeritus
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Aug 31, 2004
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62,321
Re: Exhaust Flappers

If they are the SS flappers, see if they have the rubber missing around the edges. That is what would cause the noise. Previous overheats and years of use will take their toll on the rubber covering.
The new ones are composite material and don't make the noise.
And, as you probably already know, use new gaskets when reinstalling the risers.
 

FreeBeeTony

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Joined
May 15, 2002
Messages
3,991
Re: Exhaust Flappers

Hey Don..........

I don't have to pull the risers, just the elbows in between the risers and the 'y' pipe.

Hope they come out easily.............
 

FreeBeeTony

Captain
Joined
May 15, 2002
Messages
3,991
Re: Exhaust Flappers

Removed one of the elbows yesterday and found the exhaust flapper hanging on one side. The hole in the flapper was worn right through. there were also grooves worn in the bar that the flaper rides on.

Hope to install new ones today if the rain stops!
 

Bondo

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Apr 17, 2002
Messages
71,130
Re: Exhaust Flappers

FreeBeeTony said:
Removed one of the elbows yesterday and found the exhaust flapper hanging on one side. The hole in the flapper was worn right through. there were also grooves worn in the bar that the flaper rides on.

Hope to install new ones today if the rain stops!

Good Catch,..............

If that had fallen into the Y-pipe,....... You Might have been right back where you were Last Year...............
transass.jpg

Just like This 1,.....
 

FreeBeeTony

Captain
Joined
May 15, 2002
Messages
3,991
Re: Exhaust Flappers

That's exactly what I was afraid of Bondo..........

So far it's been a pretty uneventful season as far as problems go........and this is an easy one!
 

olbuddyjack

Petty Officer 1st Class
Joined
Oct 23, 2003
Messages
318
Re: Exhaust Flappers

FreeBeeTony said:
no PM's here..........

Sorry Tony, I wanted to see if you still had that Weber carb you talked about in another thread and I didn't want to hyjack this one.

Instead of me trying to figure out how to PM could you drop me a line at: xxx ?

Thanks, Jack
 

FreeBeeTony

Captain
Joined
May 15, 2002
Messages
3,991
Re: Exhaust Flappers

Jack, check your email...........

Just got back from the boat.............new flappers installed........not a sound now.

I like those types of projects........easy to do with the right out come!
 
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