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sandm
05-17-2010, 03:21 PM
so I ran my boat on saturday and didn't have any issues. noticed as I pulled it out sunday morning that one of the exhaust flappers came off on saturday and now it's just a round hole.
my question is whether they really need to be there? seems that they must serve some purpose, but I see some boats with the turned-down chrome exhaust ports and wonder whether I really need to spend the cash to replace or not..

thoughts??

cab13367
05-17-2010, 04:09 PM
so I ran my boat on saturday and didn't have any issues. noticed as I pulled it out sunday morning that one of the exhaust flappers came off on saturday and now it's just a round hole.
my question is whether they really need to be there? seems that they must serve some purpose, but I see some boats with the turned-down chrome exhaust ports and wonder whether I really need to spend the cash to replace or not..

thoughts??

Well, I know that the ones with straight thru polished exhaust tips have internal flappers to keep water from flowing back thru them.

Waynes345
05-17-2010, 04:37 PM
so I ran my boat on saturday and didn't have any issues. noticed as I pulled it out sunday morning that one of the exhaust flappers came off on saturday and now it's just a round hole.
my question is whether they really need to be there? seems that they must serve some purpose, but I see some boats with the turned-down chrome exhaust ports and wonder whether I really need to spend the cash to replace or not..

thoughts??

I had the same issue at the end of last year and ordered a pair from Skidim.com. They were 3" and $46 for the pair. I figured they were there for a reason in the first place so with one missing I expected the other one to go and replaced them both. Here was the part number for mine:

JMS32-05018 FLAPPER 3" EXHAUST 2.00 $45.98

sandm
05-17-2010, 04:41 PM
crazy money for a rubber piece. heck, you can get the replacement part for the inside of your toilet for $5. these don't really look much different :)

guess I'll start to shop around.

zabooda
05-17-2010, 05:42 PM
They help to keep varmints out too.

sandm
05-17-2010, 08:36 PM
well, here's an interesting one. flappers are only available in mass produced 3" and 4" varieties. skiers, for whatever reason, has chosen to use 3.5" for the thru-hull exhaust ports, and they don't make a 3.5" flapper readily available(dealer told me that they couldn't even order one) so you have to take the 4" and cut it down. Now I would believe that maybe this was some sort of issue with the excat 340 engine as I think I have one of the first years they were using that engine so i'll give them some time to sort it out, but while I was at the dealership today, I drooled over a $75k launch22ssv and guess what? same 3.5" thru-hull and voila, 4" flappers cut down. really??? on a 75k boat? there are other boats in the same price range using chromed tips with them hidden, and I bet they fit like they belong...

ok, off the soapbox.

on a real positive note, $29 for a pair of new flappers plus tax... bonus....

zegm
05-17-2010, 08:51 PM
I went over 20 years and never lost one of these but at the beginning of last season I noticed one missing on our new LS. Yes you do cut down the 4" one but it is easy and it will fit nice if you do a little trimming, there are too many variations of exhaust systems to tool up one for every 1/8 diameter increment. Living on the coast in a state that has more boats per capita than any other place in the world I want to say I didn't pay much over 10 dollars for mine for a local marine supply store and it came with a hose clamp too. I asked a local boat guy if they were needed and he said YES! I am trying to remember why but it was something about sucking water into an engine if an exhaust valve was bad or something like that. But! The real point is that apparently they are either not put on very tight at the factory OR after a season they need to be checked because something has seated, broken in, stretched etc.

maxpower220
05-17-2010, 11:26 PM
They are onlly there to reduce the chance of forcing water up the exhaust when the boat is moving backward (especially when not running). The flaps are NOT water tight. Due to the the design of the exhaust system (risers) and the fact that the engine is almost always running when the boat is going backwards, they aren't "required". You must remove them to install a FAE.

zegm
05-18-2010, 12:05 AM
They are onlly there to reduce the chance of forcing water up the exhaust when the boat is moving backward (especially when not running). The flaps are NOT water tight. Due to the the design of the exhaust system (risers) and the fact that the engine is almost always running when the boat is going backwards, they aren't "required". You must remove them to install a FAE.

Not to argue but what if the engine dies when backing up because you don't have a nice fuel injected engine and the carb/engine isn't quite warmed up. Or you are backing up and for some other reason you shut the engine off while in motion, you accidently hit the lanyard switch with your knee like I did Saturday. Or like my old boat, it had marine headers on it and there was no "rise" in the system. And what happens when you have the boat on the trailer and you back the boat down into the water quickly because you are really good at backing up? Maybe they aren't required because the probability that any of these would happen is small but if water did get into the cylinders it is not compressible and damage will occur. With an FAE isn't the direction of the pipe 90 degrees to the direction that water would flow into the exhaust while going backwards. For 15 to 20 dollars it is really cheap insurance and is a simple repair/replacement. No they are not water tight but they will close and prevent most water from entering when needed. :)