Shaft slipping within Gimbal Bearing

[Brentathon]

Can the coupling end of the outdrive's shaft ("yoke assembly") spin/slip within the gimbal bearing? Because I hear a strange sound at high rpm's (+3800), and I noticed that my O/D's shaft was rusty directly aft of both O-rings (right up against the yoke), I'm not sure why.
The gimbal bearing felt perfectly smooth with no play, however it was somewhat tight (not free-spinning like a bike wheel).
It's tough to describe the sound...kinda like a fluttering "shhhhh" sound...definitely sounds like it's from a rotating element....maybe PS pump???
Engine is 1990 5.7 Alpha. Waterpump new, alternator new,.

 

[dubs283]

Re: Shaft slipping within Gimbal Bearing

shaft was rusty on the bellows side of the gimbal bearing??

water in bellows at some point??

did you replace the two o-rings when re-installing the drive?? and a complete gasket kit for that matter??

 

[Brentathon]

Re: Shaft slipping within Gimbal Bearing

Shaft was rusty only between the aft-most o-ring and the yoke. The rest of the whole u-joint was fine. It looked like it may have spun some, and it turned rusty (I should have taken pics).
Drive is a SE106 from 2008-ish, reman engine from 2007 (including new Y-pipe, starter, and flywheel).
Water has never been in bellows.
Replaced both o-rings, and even the bigger one, which I guess is not required anyway.
Think I first heard this sound 2 seasons ago.....I just usually don't run much over 3700 rpm, anyway.
Before this season, I replaced Upper swivel shaft/seal and both upper/lower bushings in Gimbal Housing, lower swivel pin, all bellows, shift cable, shift shaft and seal in Bell Housing, just replaced alternator, last season replaced engine circ pump and T-stat housing......there's very few original components...:facepalm:

 

[dubs283]

Re: Shaft slipping within Gimbal Bearing

i would have a helper drive the boat while you inspect the engine compartment for the noise, could be any number of things from your suggestion of the PS pump, circ pump, gimbal bearing/u-joints or even your SEI drive