Failed Exhaust Flappers
 

While winterizing my boat this weekend I had to start and run the boat after I changed the engine oil to check the oil level. I noticed a knocking sound coming from the starboard side of the engine while in the boat with the hatch up. Turned out to be coming from the exhaust. Upon further investigation I noticed that the flapper in the port side exhaust was only 50% intact while the starboard flapper was 100% intact. I contacted Nordic and they informed me that that knocking sound is prevalent with the flappers 100% intact.
Obviously I need to replace the port side flapper and the question I have are these prone to fail and how many Nordic owners have verified their exhaust flappers are still 100% intact?? My boat (07 Rage w/496HO w/ 80hrs) has the exhaust coming out of both corners of the transom. I just stuck my hand inside the exhaust outlet and could feel the condition of the flapper.

Thanks

Steven

i only have half of the flaps on both sides, i had this exact problem with my imco tips as well, the rubber ones WILL fail in a short period of time, only remedy is to get stainless flaps which i don't know if nordic has them, may be able to get some and put them in yourself, i don't worry too much since there is some bends in the exhaust and i always ease back when falling off plane to avoid the wall of water washing over the transom

Just about every Nordic I've seen with corner exhaust has flappers broken. They are made by IMCO. I replaced numerous ones but finally just gave up. I've only seen one engine damaged from water ingestion (2004 Rage 496) and I found flappers missing. Can't say for sure that was the cause. Probably other contributing factors also.

Bob
Full Throttle Marine