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When should you replace the Gimbal Bearing?

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gonflyn

New member
Hey, I have seen a lot of a instructions and videos on how to replace a Gimbal Bearing on a Mercruiser Sterndrive. My question is, "When and why (or Both) should the Gimbal Bearing be replaced? How will you know if you need to, what are the symptoms of a bad Gimbal bearing? Or is it a preventative maintenance item to do at fixed intervals?
 
The main symptom is when running in gear in the water, you turn you steering almost all the way to either direction like making a turn and you will hear/feel a grumbling/growling sound/feeling.

Replace ONLY as needed. Mine in my 1987 boat as far as I know is original and I have owned the boat since 1995

Now if you service your outdrive every year ( remove it to grease ujoints and do a general check) (if your ujoints are serviceable) then you simply stick two fingers through the bearing and feel it. If it is not smooth then replace it.

The service part is based on year of the boat. newer models (I forget the year it changed but in the 90's) went to non serviceable ujoints. No greasing required the need to remove the drive is somewhat not done any more.

Me I remove the drive no matter what. I check and grease the gimbal bearing if it is grease-able as the newer ones are no longer grease-able.
I manually grease the input shaft and replace all gaskets and o-rings and do a general inspection. It also will show after sitting all winter if the upper carrier bearing decided to leak and leave a lot of gear oil in the bellows.......
 
If your gimbal bearing is serviceable (meaning that there is a grease port that directs new grease into the bearing), be sure to do this dynamically.
In other words, add grease with the engine operating at idle speed.
Doing this dynamically helps ensures a more complete exchange of old for new!

And NO...... you will likely not see this being suggested in an OEM service or workshop manual.


.
 
Hey, Thanks for all the info. After taking my Upper unit off.....due to the gears being toasted, It at least looks like the Gimbal bearing and everything else looks to be ok. Other than the fact when it was put back together, the guy used RTV Silicone instead of a gasket?

I do have one additional question, there are two holes in the Bell housing, that were filled with the RTV? One is just above the right top mounting stud, and the other lower left below the Water line? What are these for? The lower one looks like it's not a through hole...can't tell with the top yet, got to pull out all the Silicone?
 
my 87 alpha one was a little stuck coming off.No water leaks .Did noticed gimball looked a little dry on grease.I did grease it every season before docking..I did not hear any noise from gimball during use.I did notice some irreguarilty turning the gimball ,not looseit was suppose to have been replace 4 yrs ago
Does the bearing need replacement?
thanks
john
 
john1947 said:
my 87 alpha one was a little stuck coming off.No water leaks .Did noticed gimball looked a little dry on grease.I did grease it every season before docking..I did not hear any noise from gimball during use.I did notice some irreguarilty turning the gimball ,not looseit was suppose to have been replace 4 yrs ago
Does the bearing need replacement?
thanks
john
Click to expand...
Hard to tell from here, by irregularity’s what do you mean rough? I usually grease mine while idling on the muffs to get grease through out the bearing. Would think no it doesn’t need replacement but you want to turn it while greasing to make sure fresh grease gets in
 
Dieter said:
Hard to tell from here, by irregularity’s what do you mean rough? I usually grease mine while idling on the muffs to get grease through out the bearing. Would think no it doesn’t need replacement but you want to turn it while greasing to make sure fresh grease gets in
Click to expand...
I think it needs a through greeting first check later
Thanks
 
Shaking hands with a mechanical object will not answer your question.....

Spell check!!

""Thorough Greasing"""
 
kghost said:
Shaking hands with a mechanical object will not answer your question.....

Spell check!!

""Thorough Greasing"""
Click to expand...
I always talk nicely to my bearing before install....

Seriously to OP removal all the old grease you can, if solid it may be sign of water intrusion...

Spin the bearing while you grease it to expel all the old grease whip off any excess in there as that can insulate the bearing.

Be happy you still have a greasable one... I just replaced the non greasible u joints on my gen two drive two of the legs of each cross the grease was dark and had ridges worn in them. Lubed for life.... a short life only 300 or so hrs on it never got water in bellows...
 
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