Mercruiser Outdrive Noise

[SS MAYFLOAT]

I have a 89 alpha 1 that has a slight vibration and a growl only when its in forward or reverse. At 2000 rpm and lower it is noticable, over that power range it doesn't vibrate or make any noise. I pulled the lower unit a couple of weeks ago and found nothing in the bearings. Everything looked fine. In the upper unit, I removed the top cover and everything looked new since it was rebuilt about 150 hours ago. When draining the lube, no metalic was seen and no particles found. Even in the housing when I pulled the output shaft out there was no metal particales. Wear patter on the gears is right in the middle just where it should be. Will the gimble bearing behave like this? Thanks

 

[Trent]

Re: Mercruiser Outdrive Noise

I dont know much..But if it were me I would pull the outdrive and check the gimble and the u-joints again. Try doing hard turns left and right does the noise get worse?

 

[SS MAYFLOAT]

Re: Mercruiser Outdrive Noise

When turning the wheel to hard left or right it doesn't make any difference. Only when the outdrive is up all the way, but to me that is common for the U-joints to growl. This noise is only when it is in gear, forward or reverse, it doesn't matter. When the boat is on the trailer, with muffs on, it sounds okay, and no vibration. Also I changed props with a new one fresh out of da box, no difference. One tech in the area seems to think it is the lower bearing in the upper unit, but with no tell tale signs of particales in the lube, its hard to believe it is a bearing. The U-joints were replaced when the outdrive was rebuilt. As a service tech, I know just because parts are new don't mean that they are good. <br /><br />I'm going to pull the complete unit next week after we get back from the lake. I still have my cabin cruiser to enjoy, so all my boating still continues. My son likes to tube/ski, but the boat is just a little too big (27')to be doing that with. That is what the broken boat is for. Thanks Trent for the info.