Ticking noise seemingly from exhaust

I have just bought in mid September a 97 Wellcraft Martinique 2800 with a Merc 7.4 EFI, 400 hours, Bravo 3 drive, engine serial:0K151492, drive serial:0K182146 used in saltwater which has developed a loud ticking noise. On the way back in this past Sunday it started as a very quiet tick with a frequency at roughly twice the engine speed I could barely hear until the last time I came off of plane. Time between barely audible and quite loud is less than one hour of runtime, if that. Now it does it all the time in or out of gear but oddly is louder off the back of the boat than from the engine compartment. Performance is completely unaffected. I have lurked a ton around here for months just to soak up as much as possible before I actually bought this boat so I knew what I was getting into and my research from here has led me to believe the exhaust shutters are making this nasty racket, does this sound correct? Is there anything I can do to verify? If they need replacement where do I find them, not only on the boat, but to buy from? Better to get Merc ones as opposed to aftermarket if even an option? Is this a job for an amateur like myself? Am I even remotely correct? And on a side note I would like a Mercruiser service manual before I touch anything especially with winterization around the corner, I have read I should find a Merc one because the Seloc's are iffy as are others. Any help is obviously appreciated. Thanks.

Re: Ticking noise seemingly from exhaust

I had one of those sounds and it ended up being the exhaust gasket.

Re: Ticking noise seemingly from exhaust

I've decided to replace the exhaust shutters given they are cheap and my research has led me there. Even if I am wrong they are almost certainly original. My service manual has not arrived yet and may not make it here before Sunday when I will attempt this. It doesn't seem that difficult but this will be my first repair on a boat so I'm wondering if there are any special tools needed or even any advice before I begin. Appreciate any help. By the way all the gasket do not seem to be leaking to me.

Re: Ticking noise seemingly from exhaust

I have never personally replaced these but from what I have read you need to pull the engine to replace the shutters. If its ticking louder outside the boat it may be in the outdrive.....or even the gimble bearing...or the u joints

Re: Ticking noise seemingly from exhaust

choochooharley said:

I have never personally replaced these but from what I have read you need to pull the engine to replace the shutters.

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You only have to pull the engine on the old 3 piece y-pipes. The newer 1 piece y-pipes the shudders are at the top and the engine can stay in. But i bet the ol clakity noise is from the shudders... good job troubleshooting and goodluck!

Re: Ticking noise seemingly from exhaust

choochooharley said:

I have never personally replaced these but from what I have read you need to pull the engine to replace the shutters. If its ticking louder outside the boat it may be in the outdrive.....or even the gimble bearing...or the u joints

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Which is exactly why I immediately crapped my shorts until I noticed the noise was completely gone when cruising and only heard when off plane and in neutral. Also, when underway, there is no growling or abnormal noises when turning, thankfully.

Re: Ticking noise seemingly from exhaust

Ah what every boater needs a change of skivees.

Re: Ticking noise seemingly from exhaust

How the hell do these damn elbows come out!? I can wiggle these all over the place after screwing with it for an hour but they're not even close to coming out. What's the secret?

Re: Ticking noise seemingly from exhaust

WellyMart97 said:

How the hell do these damn elbows come out!? I can wiggle these all over the place after screwing with it for an hour but they're not even close to coming out. What's the secret?

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Ayuh,... Loosen all 4 hose clamps(both ends of the elbows)...
Slip a hose pick or screwdriver between the metal, 'n rubber to release the grip...
Then lift the aft end off the y-pipe, 'n pull the elbow back from the risers...

It helps to push the aft rubber coupler down onto the y-pipe as far as possible....

Re: Ticking noise seemingly from exhaust

Aha, gotcha. Thank you.

Re: Ticking noise seemingly from exhaust

Check your Spark Plugs and distributor cap wires for arching. I had the same thing and found both arching. Changed wires and cap and Walla...Ticking Gone

Re: Ticking noise seemingly from exhaust

Shudders replaced and ticking noise gone - checked for arcing, but didn't find any but thank you. However I also apparently had a much quieter clunking noise from the transom area which I couldn't hear over the other noise that gets a bit louder in gear HA!! How unlucky is that!? Guess when the drive gets pulled for the winter I'll have to check things out. I thank everyone for their help.