1999 BowRider 180 rattle in engine compartment

[TommyRox]

I have a 1999 BowRider 180/3.0 and I am starting to hear a metallic rattling in the rear of the engine compartment. I only hear it when the engine is idling and it sounds like a metal plate or housing that is coming loose. If I give it a little throttle and the engine smooths out it goes away. It sounds like it's coming from the far end of the motor and underneath where the motor and drive meet and I cannot hear it from the outside.

Is there a plate or housing back there that might be the culprit?

Any advise or feedback will be greatly appreciated.

Thomas

 

[Knotty Buoy]

Exhuast shutter?:huh:

 

[annie]

You could try greasing the shaft coupler..... Turn the engine over by hand until you see the grease nipple at an accessible location (rear of engine).
Check tighten the bolts on the coupler plate also.

 

[MasterFab]

It is very likely the exhaust flapper. The noise will be apparent at idle, but will disappear under load. Mercruiser makes the exhaust flappers from steel, and coats the outer edge with rubber. Over time, the rubber degrades and falls off, and the flapper will contact the exhaust tube directly, resulting in a random "ticking" sound that can be quite loud. Remove the elbow and hose from the exhaust tube, to expose the top of the tube, and take a look at the flapper. If the outer coating of rubber is gone, you found your noise.

And if it hasn't been done in a while, it's a good idea to grease the coupler too!

Dale

 

[TommyRox]

Super responses... I won't have a chance to check your suggestions for the next few days but will let you know what I found out.

 

[beernutz]

This is probably not the problem but I'll comment just in case. I had a rattle in my engine compartment and it turned out that the screws holding the hinge that the compartment pivoted on had become stripped and/or bent and therefore were not holding the hinge down solidly. I used some plastic wood to strengthen the floor under the hinge then replaced the damaged screws with slightly wider, longer ones and the rattle is now gone. YMMV.

 

[TommyRox]

Thanks for all the posts - it was indeed the exhaust flapper

http://share.shutterfly.com/action/welcome?sid=0ActmzRkzZNWjjo

Now I have another issue. I am getting water leakage from the riser and manifold when I put it all back together. I replaced the gasket and used RTV 2 times and had a leak. I called SeaRay and they advised to install gasket dry...bigger leak. Any ideas as to get this from leaking?

Thanks in advance for all assistance

TommyRox