Squealing noise in neutral

[Andy J]

Finally got the sterndrive on after a lower shift cable issue with the help from everyone here. Replaced the lower impeller unit as it was damaged and pulled the engine as parts were missing from the rear engine mount hardware. Put all back together and checked alignment with alignment tool and adjusted, slid in and out with 2 fingers.
At home on the muffs and on the lake today have a squeal noise that didn't have before. We ran the boat 3 hours on the lake and ran well.no noise while in gear... Still have the noise coming back in only in neutral..... any ideas?

TIA Andy J

 

[achris]

Pull the drive off (only take a few minutes), put a garden hose in the water hole on the bell housing, and fire up the engine. Noise still there? It's an engine noise. Noise gone, it's a drive noise (or gimbal bearing).

Does the noise change if you swing the steering wheel to one side or the other? Same in the centre as sides? Are your belts in good condition, and correctly tensioned?

Chris...

 

[Andy J]

Chris,

Good idea to remove the drive to isolate the problem, will try it today and let you know.

The noise doesn't change moving the steering or trimming up-down so think U joints are ok.

After noodling over the noise after my post I think it may be an alignment issue between spline and gimbal bearing. Noise is from rubber bushing that holds the spline in the flywheel. When spline is loaded noise goes away. Is this possible?

How hard much force should it take to move the gimbal bearing with the alignment tool? Seen some using soft face hammer, I can move mine with 2 hands on the alignment bar but it seems stiff. Maybe normal?

Some additional info-

Sterndrive is a MC-1

Had to pry the drive off to remove initially to replace lower cable. Had gross alignment problem as rear engine mount hardware was missing and rear bolts were loose. After alignment sterndrive slid on no problems.

Andy

 

[harringtondav]

The first, forward O ring seals the grease in the engine coupler. The other two squeeze between the gimbal bearing ID and the mating engine splined shaft OD. I've always wondered about their function, and am guessing they add a little friction grab to ensure the gimbal brg. rotates with the drive shaft. If your gimbal brg. (new?) is a little stiff, or old and failing, this joint could spin at low neutral low load and squeal. When in gear that drive shaft assy is going to start side loading the gimbal brg., more with more power, even more at trim and turns. These side loads are enough to force a tight bond b'tween the gimbal brg. and drive shaft. So when you follow achris shake down, turn the gimbal brg. with your fingers. Full of new grease it will be a little stiff, but you should have no trouble spinning a good one.

 

[achris]

.....
How hard much force should it take to move the gimbal bearing with the alignment tool? Seen some using soft face hammer, I can move mine with 2 hands on the alignment bar but it seems stiff. Maybe normal?

Yep, normal. ..

 

[JoLin]

Yep, normal. ..

I'm confused. I can turn both of mine with 2 fingers on the alignment bar, not 2 hands... and they aren't stiff at all. I thought the 2-finger method was normal....

 

[achris]

I'm confused. I can turn both of mine with 2 fingers on the alignment bar, not 2 hands... and they aren't stiff at all. I thought the 2-finger method was normal....

OP is talking about gimballing the bearing, not turning it. ..

 

[Andy J]

Finally had time to remove the sterndrive today and found the source of my squeal...... First time installing a sterndrive mistake!


Bell housing seal was caught between bearing and spline shaft. At least no damage was done, Guess will have to keep nose more centered next time.

From what I have read and seen the seal is installed in the bell housing before installing sterndrive. Correct?



Thanks for everyone's advice and input

Andy

 

[AShipShow]

Oops! That will do it. I usually put a bit of marine grease on the seal to help it stay in place when installing the drive, otherwise, as you've seen, they don't like to stay there on their own.

 

[Andy J]

Oops! That will do it. I usually put a bit of marine grease on the seal to help it stay in place when installing the drive, otherwise, as you've seen, they don't like to stay there on their own.

I had grease on it, maybe need more LOL..... Think I may have snagged it having he drive too crooked during install.

Andy

 

[achris]

That seal MUST be glued into place, no grease, glue.....
Most of us use bellows adhesive.

Chris........

 

[Andy J]

That seal MUST be glued into place, no grease, glue.....
Most of us use bellows adhesive.

Chris........

That sounds like a good solution, thanks Chris!

So much to learn but getting there

Andy