Perma Lube Gimbal Bearing?!?!

[300sflyer]

I just opened up two new merc Bravo transom kits [kit # 30-803100T1] to have a look at everything.

Much to my surprise... both gimbal bearings are a "perma lube" bearing, with no hole in the outer race so it can be greased. In addition, the kit came with instructions and a plug to thread into the gimble housing, after the grease fitting is removed...

Why the ---- would Merc do this?!?! Doesn't make any sence to me.

 

[HT32BSX115]

Re: Perma Lube Gimbal Bearing?!?!

Howdy,


Well, I did a little search and found the following at http://www.sterndrives.com/precisionparts/421.html

Some cross bearings have no zirt fittings. That is because they are Perma-Lube
cross bearings which do not requires greasing. The rubber seals are usually orange.

I also found the following from a Mercruiser ad....

• Drive Lube Monitor ? Alarm warns if drive lube is low. Engine mounting allows easy inspection and fill without the cost to pull a boat from the water.
• Permalube ? U-Joint ? Virtually No Maintenance Required
• Maintenance Free Hinge Pins ? No added cost to pull a boat from the water
• Greaseable Drive Coupler ? No added cost to pull a boat from the water
• New permanently lubricated gimbal bearing does not require maintenance

My guess is that it is a permanently lubricated bearing.


regards,


Rick

 

[300sflyer]

Re: Perma Lube Gimbal Bearing?!?!

I guess what is bothering me, is that I know eventually that bearing grease will dry out, and damage the bearing as a result...

Having a grease fitting, allows fresh grease to be pumped in each year, as part of regular maintenance to prevent that from happening.

 

[HT32BSX115]

Re: Perma Lube Gimbal Bearing?!?!

Well,


Think of it like a front wheel bearing on a front wheel drive car or 4x4 GM independent suspension truck.

I have a 1994 3/4T 4x4 GMC Suburban. It has permanently lubricated front wheel bearings. It's now 16 years old and has 185,000 miles on it and I'm not really worried about it.

185,000 miles on my roughly 30" dia tires is about 125 MILLION revolutions so far......(carrying about 2000lbs weight)


A marine engine turning 3000 RPM (180,000 revolutions per hour) for 500 hours would turn about 90 million revolutions AND doesn't carry anywhere near that side load.


I don't worry too much about not being able to grease the front wheel bearings on my Sub......nor would I worry about a non-grease-able gimbal bearing..........

If it gets noisy after 500 hrs, replace it!



Cheers,


Rick

 

[mkast]

Re: Perma Lube Gimbal Bearing?!?!

How often is the drive supposed to be removed for inspection?

 

[HT32BSX115]

Re: Perma Lube Gimbal Bearing?!?!

Mercury suggests checking the alignment every 100hrs or once a year in my Bravo maintenance schedule....

You have to pull the drive to do that and the alignment tool is pushed thru the gimbal bearing at that time.....So I guess you could check the gimbal bearing at that time too....

 

[300sflyer]

Re: Perma Lube Gimbal Bearing?!?!

Well,


Think of it like a front wheel bearing on a front wheel drive car or 4x4 GM independent suspension truck.

I have a 1994 3/4T 4x4 GMC Suburban. It has permanently lubricated front wheel bearings. It's now 16 years old and has 185,000 miles on it and I'm not really worried about it.

185,000 miles on my roughly 30" dia tires is about 125 MILLION revolutions so far......(carrying about 2000lbs weight)


A marine engine turning 3000 RPM (180,000 revolutions per hour) for 500 hours would turn about 90 million revolutions AND doesn't carry anywhere near that side load.


I don't worry too much about not being able to grease the front wheel bearings on my Sub......nor would I worry about a non-grease-able gimbal bearing..........

If it gets noisy after 500 hrs, replace it!



Cheers,


Rick

I have had to replace several sealed wheel bearings on a # of vehicles I have owned. They don't last forever.

Call me old fashioned... I like having grease fittings.

 

[cr2k]

Re: Perma Lube Gimbal Bearing?!?!

Lots of things have changed over time many just because they are cheaper to build and easier to assemble (alpha gen II) not necessarily better.

My guess is takes less time to slap in a gimbal when you don't have to line up the lube hole.

As for the perm U-joints, well a majority of boat owners just don't bother to pull the drive until something is wrong. Which is good for people who make a living by repairing them.

Now that said, I am probably going to get flak over the gen II thing, but hey I have taken lots of it on here over my stringer.

 

[vxtech]

Re: Perma Lube Gimbal Bearing?!?!

i think manufacturer would rather you replaced his bearing rather someone maintaining his bearing-everybody (industry) makes money if bearing is maintained (greased) but manufacturer, if you replace bearing everybody-including Manufacturer make money-as we are a throw away society-that is limited by grease fittings and proper maintenance, and this goes for anything that has bearings not just boats, it boils down to money, thanks chris

 

[Bondo]

Re: Perma Lube Gimbal Bearing?!?!

Call me old fashioned... I like having grease fittings.

Ayuh,... Same Here.... You can always install 1 of the Greasable gimbel bearings,.. They're still available...

 

[ENSIGN]

Re: Perma Lube Gimbal Bearing?!?!

cr2k hit it right on the money,Most of the slip customers here don't even read the owners manuel !!!

 

[300sflyer]

Re: Perma Lube Gimbal Bearing?!?!

Ayuh,... Same Here.... You can always install 1 of the Greasable gimbel bearings,.. They're still available...

When comparing the new bearings with an old one with I have, the only difference appears to be the hole in the outer race.

Has anyone carefully drilled a hole in one of the new ones?

 

[300sflyer]

Re: Perma Lube Gimbal Bearing?!?!

Well, I just answered my own question...

Check out the picture of the new bearing, next to an old one.

 

[Don S]

Re: Perma Lube Gimbal Bearing?!?!

Ones sealed, the other isn't.

 

[300sflyer]

Re: Perma Lube Gimbal Bearing?!?!

Exactly... and cannot be modified.

 

[Don S]

Re: Perma Lube Gimbal Bearing?!?!

Exactly... and cannot be modified.

Then install them the way they are, they will work fine and it's what they use on the new drives. If they go bad, replace them with a Sierra 18-2100, they are greasable.
Of course if you just want to rant about it, throw them away, and put the Sierra replacements in right now.
About the only thing that kills a gimbal bearing is dirt and/or water, as long as you keep the dirt out (that's easy, it's a sealed bearing) and the water out. (Don't let water in the bellows) then they should last for many years.

 

[300sflyer]

Re: Perma Lube Gimbal Bearing?!?!

No ranting... Just pointing out the new sealed bearing cannot be modified to accept additional grease.

I will likely install the Sierra ones. Thanks for the info.

 

[Don S]

Re: Perma Lube Gimbal Bearing?!?!

Before you spend extra dollars to put in the Sierra ones, why don't you use the new ones you already own? you should be pulling the drive yearly to check them, if they are working fine, why replace them?
Then, maybe in 5 or 10 years you can reply to this thread and say how bad they are.

 

[Lou C]

Re: Perma Lube Gimbal Bearing?!?!

As long as your bellow doesn't leak I can't see them having a problem....and even with greaseable gimbles when you get water in the bellows you wind up replacing it anyway...I do prefer being able to grease things...but not making them greasable may reduce the chance of water getting in via the grease tube....not sure if that's why they did it...