Noise - normal or not?

I have a noise coming from my new to me boat with 1992 Merc 5,7 and Alpha One gen 2. I'm new to this whole outdrive thing so I'm not sure if it's normal or not.

The sound/noise is a little like that from a worn CV-joint or a timing chain tensioner failing. It's not a grinding noise and it's not a heavy clunking (like that from a con rod). There's no change in noise when I turn the wheel or apply load (points away from CV-joint) and by using the metal rod and listening to the engine it sounds all well. I can hear it from both the engine bay and from outside the boat, ie leaning over the stern.

So I'm thinking that it may be the gimbal bearing? What say you experts?

Should I continue to run the boat and see if the noise gets worse (assuming it's not normal)? If it is the gimbal or a CV, could it go from making a noise to sudden BOOM causing mighty failure of the whole outdrive/engine)?

Outdrive has been serviced with oil and impeller and there were no evidence of leaking or gear/bearing failing judging by the oil. No noise when turning the shaft and no grinding or resistance.


Thanks!

Re: Noise - normal or not?

How do you have your O/D trimmed while you are hearing this noise? Are in water, or on muffs? (how are you applying "load"? Does the noise change with RPM?) Have you greased the gimbal bearing while the engine is running to see if the noise changes?

Re: Noise - normal or not?

Thrn the wheel all the way to eithrr side if it gets real loud then it is a gimble.

Re: Noise - normal or not?

It's in the water. I didn't hear anything when we ran engine on land. I did't know the gimbal was accessible from the engine bay, I thought it was sealed. Or are there grease nipples?

Applying load as in getting in gear and accelerating.

No change in sound when turning the wheel. Hard to tell if if changes with rpm, the engine's too loud in itself.

Re: Noise - normal or not?

Could be the ujoints or the gimbal bearing. When was the last time the drive was pulled for preventive maintenance?

Re: Noise - normal or not?

Magnus Wallner said:

It's in the water. I didn't hear anything when we ran engine on land. I did't know the gimbal was accessible from the engine bay, I thought it was sealed. Or are there grease nipples?

Applying load as in getting in gear and accelerating.

No change in sound when turning the wheel. Hard to tell if if changes with rpm, the engine's too loud in itself.

Click to expand...

There is a zerc fitting on the Gimbal housing, but if your boat is in the water, then so is the zerc. (it is on the lower stbd side of the housing, next to the transom).