99 Ski Nautique muffler
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Boat Maintenance
Forum Discription: Discuss maintenance of your Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=17932
Printed Date: November-18-2024 at 2:34pm
Topic: 99 Ski Nautique muffler
Posted By: Mal
Subject: 99 Ski Nautique muffler
Date Posted: June-06-2010 at 4:34pm
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Hi all, I've just got back from a weekend ski-ing boarding etc, whilst running at between 15 and 25mph there is a loud droning sound, if you lift up the rear centre floor section and put pressure on the muffler it appears to get quieter, over 25 it seems to all but go away.
Is there anything that can be done? my suspiscions make me think that perhaps something has fallen apart internally. The hoses are not fouling anything and the self adhesive neoprene that the muffler sits on has been replaced. Can the muffler be cut open and the baffles be re-glassed? I need to sort it as my ears are still ringing 4 hours later. |
Replies:
Posted By: M3Fan
Date Posted: June-06-2010 at 9:37pm
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There is supposed to be foam padding under the muffler. This tends to dislodge over time- check to make sure that it's still there. ------------- 2000 SN GT40 w/99 Graphics/Gel 2016 SN 200 OB 5.3L DI https://forum.fifteenoff.com |
Posted By: Mal
Date Posted: June-07-2010 at 11:57am
I have replaced that with new, no difference. |
M3Fan wrote:Posted By: 8122pbrainard
Date Posted: June-07-2010 at 12:50pm
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All boats will produce harmonics at certain speeds/RPM's. Has the boat always done it? How's the condition of the prop and straightness of the prop shaft?
Yes, the muffler can be cut open and reglassed. I'd remove the baffles or go to a Y pipe completely eliminating the muffler.  ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: Mal
Date Posted: June-07-2010 at 7:45pm
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No it hasn't always done it, I haven't had it long and it was as sweet as a nut when first purchased and tried, however on my first launch i did hit the concrete slipway with the prop and bent 2" of every blade at right angles, I had it repaired but no-one seems to be able to deal with cnc machined props here in the UK. I have checked the shaft and all appears to be ok there and have had the prop repaired but as to its state of balance after the repair i can't be sure. A dealer over here has told me to put my arm down the inlets and outlet of the muffler and check the baffles as he seems to think this is a common problem and if so can be repaired through the holes.
I can get a good deal on a new Acme 422 from a dealer friend who use these props on their home built tournament inboards so will go down that road as well, come the weekend i'll pull the muffler off and have a look. I'll keep you posted |
Posted By: 8122pbrainard
Date Posted: June-07-2010 at 10:37pm
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How did you check the shaft? Considering the prop damage from the concrete ramp, I feel you should check it again especially if you didn't use a dial indicator on it. Aft of the strut, it's the only way to check it. ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: Mal
Date Posted: June-08-2010 at 7:24pm
| I'll pull the prop and put a dial guage on the shaft at the weekend and see what i find. |
Posted By: Scrawford
Date Posted: June-10-2010 at 3:02am
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Mal,
I had a similar problem and I didn't discover it until I removed the muffler to patch a crack in the top. Upon removal I noticed a clanking sound when turning it over...the midpipe had broke loose of the top and bottom of the muffler. I repaired it myself for about $35. I have a post a couple up from this that talks about it. ------------- Eric 97 196 Closed Bow |
Posted By: kapla
Date Posted: June-10-2010 at 2:41pm
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100% chances your shaft is bent at some point....
It takes a small hit to bend this things..been there a couple of times... ------------- <a href="">1992 ski nautique |