Hey all - I have a 2004 Lightning 21 XS with a 350 Mag MPI and through transom exhaust. On the starboard side the flap inside the pipe is rattling like crazy when the motor is at idle. If I reach inside the exhaust and wedge the flap so it's stuck open, the noise is gone. Port side is not stuck open but not making any noise. I do have internal flaps as well as rubber flaps on the outside. What can be done about this noise? Here are a couple pics of it.


Edit: Apparently I am not allowed to post any pictures on this forum until I have at least 10 posts.

Mine rattle too.

Is there a better tip to replace them with that wont rattle like this?

I've used the Dana Marine tips on past boats. Really nice tips and their internal flappers do not rattle. And the flappers are bolted in so you can replace them however.... I went to order a new set a coupe months ago and found out Dana marine is no longer around. I think one of his partners or employees took it over. Now called Marine Industries West. I placed the order online and got a phone call a month later stating they were on back order. I called a couple months later and they said no stock still. after another month I gave up and bought a set of Eddie Marine.