Bravo III Outdrive rattle

[dmp240da]

I have a 2006 SeaRay 240 DA with a Mercruiser 350 MAG Horizon Bravo III.

Upon starting it this spring after winterization I noticed a rattle (ticking sound) coming from the bell housing area. I call it a rattle but it is not real loud (i.e. you don't hear it at the helm). The details are as follows:

1. I was running it on the lift, out of water, with a hose attachment.
2. Whether the drive is full left/right or full trim up/down (not trailer, of course or whether it was in gear or not had no effect on the noise.
3. For the interesting part, the noise does not start until engine was close to fully warmed up (3-4 minutes). After letting it cool and restarting once again no noise until engine warm.
Noise appears to be linked to engine speed.
I do not notice any vibration, rattle or ticking or internal noise (other than normal bearing rotational noises) when placing ear against side of upper unit adjacent to vent screw location.

Based on the engine temp. component of this mystery I have wondered about exhaust shutter noise but noise "seems" above the exhaust tube location.

Any thoughts on this would be most appreciated. Thanks!

 

[Don S]

Re: Bravo III Outdrive rattle

You might want to check your engine oil level. If it's too full, the crankshaft can hit the oil which will aireate (sp) the oil. This will cause the lifters to tick a little after the oil gets aireated. But will clear up when shut off.

 

[dmp240da]

Re: Bravo III Outdrive rattle

Thanks, but this is a noise that is coming from the outdrive not the engine. Engine is very quiet. It does seem to develop after the engine has been running a few minutes and I wonder if when the outdrive warms slightly if the cone clutch or other parts might be moving a little causing the noise. Drive shifts very smoothly and as I indicated in my original post the noise does not change relative to steering position or trim position.

Thanks in advance for any more ideas!

 

[Don S]

Re: Bravo III Outdrive rattle

You can hear the backlash in the gears rattle when they are warmed up. This is very common on diesels, but seldom heard on gas engines unless the engine is not running very smooth (a miss??).

 

[dmp240da]

Re: Bravo III Outdrive rattle

Thanks for your posts Don S.

Do you think it might be clutch rattle and as they warm they start to move more freely and begin to rattle.

Like I said, the rattle occurs in or out of gear (of course, no load as boat is out of water).

I'm just trying to figure why it takes a few minutes at idle (or slight increase to about 1000rpm), --not too fast since on muffs, for the rattle/ticking to be heard. It does not do it immediately after a cold start.

Thanks for your input!