Question about exhaust flappers

rbezdon

Senior Chief Petty Officer
Joined
Jun 20, 2004
Messages
689
While I had the exhaust system off to pull the heads I double checked to see if the flappers are still there and functioning OK. They both are in good condition and seem to rotate freely but I did notice that the holes in the "Y" pipe that the shaft go through seem to be worn pretty badly. I can, by rotating the flapper with a long screw driver, get the flapper to shift on the y pipe bore enough to not fully open, only maybe 3/4 of the way and because the shaft shifts a bit off center it can't open more. It does not stick there. I can not see any way of repairing this short of replacing the y pipe and I really dont want to pull out the whole shooting match again, heads are bad enough. I would think the normal vibration from running and bounching would keep this from happening when running but what do you all think?? Do I need to replace the y pipe just to get the flapper shaft hole a little smaller??
 

bigbrownbuku

Master Chief Petty Officer
Joined
Sep 17, 2004
Messages
885
Re: Question about exhaust flappers

the grommets are missing. they are available as a part separately. they fit neatly in the holes you describe. the flapper shaft sits inside these bushes.
 

rbezdon

Senior Chief Petty Officer
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Jun 20, 2004
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Re: Question about exhaust flappers

Thanks Ben, I'll see if I can get new ones before I reassemble it.
 

ziggy

Admiral
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Jun 30, 2004
Messages
7,473
Re: Question about exhaust flappers

vatter41, i don't know yer set up but think i understand what ya are saying pivot shaft holes. maybe the fact that yer flapper only closes 3/4 of the way is not of big issue. we talked in another thread about that they only slow the water down, that's at least mostly closed. i myself would worry that they may just plain fall off though.(depends on how long the shaft and how much engagement with the holes i suppose) when the shaft holes get worn, the shaft that goes thru it can wobble around, enlageing the holes more yet. as it vibrates it gets to the point that perhaps the shaft can find a point that the shaft drops out of one of the holes. then it will cause ya problems i'd think. i'm just sayin that mech. things that fit in holes that are worn out tend to wear to a point of no return. <br />you've read a few of the flapper posts i think. depending on yer style of boating maybe ya don't have to have a flapper. my old skow had no flappers when i got it. didn't even know it as i got it from dad. it sat in the lake all summer long w/o much use by him in his last couple of years. i ran it that way for quite a few runs w/o problems. personaly i boat on the river if i can. so i did replace my flappers when i did the maniflod and riser as i wanted the best chance i can have in the style of boatin i do....... time will tell if i pay for puttin flappers back on. it seems like they are designed to fail and cause problems from what i read about them...... i don't know of a good repair. i just think yer gonna have to have new metal put back somehow to make the holes smaller again. or rotate the shaft a bit and make new holes in fresh metal, remove it or replace it or worry about it for doing nothing. good luck and sorry to read yer havein the boatin blues.it never ends i don't think........well, that's my 2 cent's worth. jim
 

ziggy

Admiral
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Jun 30, 2004
Messages
7,473
Re: Question about exhaust flappers

cool, missing bushes. that sounds like a real proper repair to me. much better than my guess. jim
 

rbezdon

Senior Chief Petty Officer
Joined
Jun 20, 2004
Messages
689
Re: Question about exhaust flappers

Ben, thanks a ton. I have looked at the diagram several times and never noticed the bushings before. By the way, does anyone know the OMC part number?? I found them on Dour Russel but only get their part number and they have a 30 minimum plus shipping. Maybe I can find them locally for less. DR part number was 1988 5.7L exhaust item #33 0911872.
 

Phantom17

Petty Officer 1st Class
Joined
Feb 7, 2005
Messages
343
Re: Question about exhaust flappers

If ya get that stuck let me know. I live about 1/2 hour from there. If you pay them over the phone, maybe we can work something out and I can ship them to you, usps priority. <br /><br />Also try:<br /><br /> http://www.monahansmarine.com <br /><br />Ask for Julie in parts. I don't think they have a minimum to ship, but don't quote me on that.<br /><br />mnehky@yahoo.com<br /><br />-Jeff
 

rbezdon

Senior Chief Petty Officer
Joined
Jun 20, 2004
Messages
689
Re: Question about exhaust flappers

Thanks for the offer Jim, I am going to try locally (seems like they should be here in Chicago somewhere) but if I cant find it I may take you up on your offer.
 

rbezdon

Senior Chief Petty Officer
Joined
Jun 20, 2004
Messages
689
Re: Question about exhaust flappers

found out JR part number is the same as OMC
 

Phantom17

Petty Officer 1st Class
Joined
Feb 7, 2005
Messages
343
Re: Question about exhaust flappers

put a 0 in front of omc numbers at Doug Russell.
 
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