why would a gimbal bearing get stuck on a shaft?

stang32

Chief Petty Officer
Joined
Jul 16, 2004
Messages
513
when i pulled this drive i had to pry it off. i put s new one in, aligned the enginez9which took several turns down, which i thught, ok, theres the reason. i installed the drive and it fought me the last 1 inch, i pulled the drive only to find the new gimbal come out stuck on t he shaft again.
the shaft looks ok, and before i assembled the unit, i slid another shaft through the gimbal bearing into the coupler to check alignment further. it was ok as well. ifi didnt know better i felt the o rings were stuck in the bearing.
the originasl bearing had to be air chiseled off, the new one, came off with a couple shots of a hammer.
 

AShipShow

Lieutenant Commander
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Jul 8, 2016
Messages
1,803
Shafts don't get bigger over time, but if it has a nick in it or corrosion, it can actually make the OD seem larger than its supposed to be. Does the outdrives input shaft have any gouges or anything where it goes thru the bearing?
 

greno

Petty Officer 2nd Class
Joined
Nov 23, 2012
Messages
182
Take the o-rings off and run some emery cloth around that shaft. You've got some grit somewhere on there.
 

Bondo

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Apr 17, 2002
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i installed the drive and it fought me the last 1 inch,

Ayuh,..... That right there told ya there's a problem,.....

Donno what it is, never ran across such a thing before,....

I guess I'd start with greno's idea, 'n see what's bindin' up, 'n where,.....
 

stang32

Chief Petty Officer
Joined
Jul 16, 2004
Messages
513
yes Bondo, thats why i removed it, because it was soo difficult. i felt that there was another issue i needed to look at.

yes the tolerance ring is on the bearing

ths shaft does not appear to have any gouges of any kind on it.
i swear, i get some real doosy's
 

harringtondav

Commander
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May 26, 2018
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2,520
I've changed several gimbal bearings, and they always come out hard, requiring a slide hammer, or plate puller. If your gimbal bearing comes out with the out drive, it is not installed correctly. It needs the tolerance ring, proper orientation to the grease hole, and needs to be driven to bottom. Approx 1/8 of its bore should be visible from the rear/outside. The gimbal bearing is a self-adjusting bearing. The outer race has a spherical surface, allowing it to move in the female spherical surface in the aluminum hsg. The center line of the bearing can be forced out of position during installation. This can set you on a wild goose chase trying to get alignment. If you have to force the out drive home, you are not aligned.
 

stang32

Chief Petty Officer
Joined
Jul 16, 2004
Messages
513
thanks for that info but i have installing gimbal bearings down pat, the bearing was in right, the alignment was spot on, yet the drive would not go in the last 1.5" without forcing it. thats why i pulled it to check again. as i said earlier, the original was stuck to the input shaft as well, which required an air chisel to remove from the shaft. so i am trying to wrap my head around why these bearings are getting hun up on this drive. there are no nicks, burrs or anything obvious. once i have a new bearing i will be checking to see how it goes on the shaft before installation.
 

Scott06

Admiral
Joined
Apr 20, 2014
Messages
7,338
Does yours have an oring that seals the drive shaft to the gimbal? If so was the wrong oring used causing an interference fit w gimbal bearing ? As you know the drive gasket kit has extra o rings to cover many drive years
 

thumpar

Admiral
Joined
Jun 21, 2007
Messages
6,138
What drive do you have? On my Bravo I have to use the bearing that has the rear face (drive side) shaved a little bit. I don''t know if it would cause it to stick if it was the bigger one but something to throw out there.
 

harringtondav

Commander
Joined
May 26, 2018
Messages
2,520
Use a good digital/dial caliper and measure the gimbal brg. bore, and shaft OD. Gen 2 gimbal brgs. are 1.3750 ID, and the shaft and alignment tool are 1.3735 OD. Or try sliding the gimbal bearing onto the shaft before installing it. It should slide freely w/minimal clearance. Also, try pulling the gimbal bearing after you install it. It should be take much more effort than it does to pull the outdrive with the bearing stuck air chisel tight.

Is it possible a gimbal brg. ever froze, spun in the gimbal plate, and on the shaft? This could cause a loose fit in the plate, and have galled the shaft to cause interference.
 

stang32

Chief Petty Officer
Joined
Jul 16, 2004
Messages
513
just an update, there appears to have been a burr on the shaft, after hitting it with some emery cloth, i was able to work the bearing down the shaft, a little at a time. there were several areas where the bearing got hung up but i was able to sand away all the burrs. the o/d slid right on the gimbal once i had it all together nicely
 
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