Internal Flappers
#1
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I just purchased 4 of the Hardin-Marine slide in 4" flapper in cased in a stainless housing that slides over the inlet side of the exhaust tip or pipe before the transom.
[ATTACH=CONFIG]544649[/ATTACH]
Upon start up on a garden hose it sounded like a rod knock. It then got quieter with water flow. It also seemed to quiet down the engine noise like a muffler. After boating for a few days the noise got a lot less. I looked up my exhaust pipe and noticed the bottom part of the flap was not resting against the ss housing like it was during installation , It seemed to bend out a bit. So now i'm wondering if i can trust this type of setup. Is it going to let water by or is it going to shut closed. I don't like these./.. So
After searching the net I found another type of internal flapper made by stainless marine. Has anyone used this type?. Do they make any noise especially knocking sounds. These are 3.5" long and they slip into the 4" exhaust hose
[ATTACH=CONFIG]544648[/ATTACH]
Any suggestions here. I have very little room between my exhaust pipes and the transom.
[ATTACH=CONFIG]544649[/ATTACH]
Upon start up on a garden hose it sounded like a rod knock. It then got quieter with water flow. It also seemed to quiet down the engine noise like a muffler. After boating for a few days the noise got a lot less. I looked up my exhaust pipe and noticed the bottom part of the flap was not resting against the ss housing like it was during installation , It seemed to bend out a bit. So now i'm wondering if i can trust this type of setup. Is it going to let water by or is it going to shut closed. I don't like these./.. So
After searching the net I found another type of internal flapper made by stainless marine. Has anyone used this type?. Do they make any noise especially knocking sounds. These are 3.5" long and they slip into the 4" exhaust hose
[ATTACH=CONFIG]544648[/ATTACH]
Any suggestions here. I have very little room between my exhaust pipes and the transom.
Last edited by 35fountain; 08-27-2015 at 08:00 AM.
#2
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Haven't used either type but Stainless makes some quality stuff IMO. The Hardin ones you have should still slow down the back rush of water a bunch because of the design. Nothing is 100 percent. Figure your using this type instead of the external rubber flapper because of the looks, but even the rubber ones will pass some.
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#5
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they are useless for me. I had a issue with water a month ago due to my setup.[ATTACH=CONFIG]544659[/ATTACH]
Notice the holes at the bottom. That's where the water comes out with the muffler in the closed position. So the external rubber flapper on the outside does nothing
Notice the holes at the bottom. That's where the water comes out with the muffler in the closed position. So the external rubber flapper on the outside does nothing
Last edited by 35fountain; 08-28-2015 at 08:18 PM.
#6
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I have the stainless marine on my boat.... the picture doesn't show the rubber tips mine have or had I should say... they didn't last long.. and neither did the internal flapper... at about 35hrs one of the flappers disappeared.... fell out! I then put the clamp on rubber flappers on....
#8
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The rubber wears off it doesn't burn off with water exiting through them... once it wears off they make a racket at an idle.... but for one of them to just fall out? I won't be buying another set..
#9
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At least these will open not like the ones i have. The material bends from running at higher rpms but when you shut off the engine it doesn't retract, stays open a bit and I'm worried water will pass up there again. I'll have to inspect them when they arrive..Didn't you call customer service and tell them the rubber wears off and one fell out. Stainless marine makes some nice stuff..How can that happen?
#10
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I really didn't care that it fell out...I plan to take the other one out now that I added the external rubber Flappers... without the rubber tips they still work fine but do make a racket when idling....Under 40 hours & the rubber tips are pretty much shot... sounds like you can not use the rubber Flaps so these will work for you I'm sure.... better than nothing anyway right?
edit... now that I look at what you've purchased it is not what I have... my internal flaps are built into the tip.... not an add on...
edit... now that I look at what you've purchased it is not what I have... my internal flaps are built into the tip.... not an add on...
Last edited by GRH; 08-28-2015 at 01:36 PM.