Greasing wheel bearings

[jimbob669]

Is there a such thing of over-greasing wheel bearings on a boat trailer? I am not talking about packing the wheel bearings but adding grease through a bearing buddy. I have heard that nothing can be overgreased then I have been told that too much grease could blow out a seal. What's the truth?

 

[carrotsnapper]

Re: Greasing wheel bearings

I have wondered that myself. I lost a bearing buddy this weekend and wondered if it was too full of grease and popped off. I got home by cutting the bottom off a water bottle and taping it to the hub to cover the bare bearing. It was still there a hundred miles later when I got home. I was amazed. Not my idea however, I wish it was. The zebra mussel marshal that checks your boat for contamination gave me the idea. It worked though.

 

[dingbat]

Re: Greasing wheel bearings

Yes, you can over grease a bearing.

NOTE:
For best results, ample space is essential in the housing to allow room for excess grease to be thrown from the bearing and for heat dissipation. It is equally important to retain the grease around the bearing. Normally, the housing should be 1/3 to no more than 1/2 full of grease during bearing assembly. Too much grease in the housing may cause excess churning of the grease and high temperatures.

http://www.timken.com/en-us/solutio...apered_Roller_Bearing_with_Grease_English.pdf

 

[ziggy]

Re: Greasing wheel bearings

i don't see how, by injecting grease via brg. buddys that you would get to much grease in there.
i feel that when i do give the zerk a few pumps of lub that all i'm doing is pacing new grease into the outside of the hub. i don't think the new grease makes it all the way back to the inner wheel brg. i bet it hardly penetrates the outer brg. even.

while i have brg. buddys and like them ok. i feel that the inital packing and filling of the cavity between the brgs is about as good as it's gonna get...

i repack my wheel brgs. once a year (using a wheel brg. packing tool). full disassembly. then i feel confident that i'll be good to go for the season. 2 seasons is too long to wait for a full packing. i lost an inner brg. while on the road trying to get two years out of mine.. very dangerous and a real bummer to R&R a wheel brg. at the boat ramp when i'm supposed to be out boating..

 

[tmcalavy]

Re: Greasing wheel bearings

If you put too much grease into your BB, it will simply sling out after the wheel/hub heats up a bit on the road...and that lovely grease will find its way to your wheel/rim, trailer, and maybe your boat. Follow the BB label directions...been there, done that, have the grease cleaner T-shirt.

 

[SangerTom]

Re: Greasing wheel bearings

I just had my trailer serviced yesterday and asked the tech about bearing buddies. The buddies do not grease your bearings. All they do is create a pressurized area that stops water from entering into your bearings.

He explained that when your bearings are hot and you back your trailer into the cold water, the hot bearings want to suck water in to cool them off. The bearing buddie should keep around 3lbs of pressure max to stop the water intrusion.

He said check them before you launch. The blue ring should be about 1/8" out from the stainless retainer clip. If you put too much grease in the buddie it will blow out the back seal and be worthless. Maybe one or two pumps.

Don't put grease in before the trip - does nothing for the bearings - but potentially ruins the bearing buddy.

 

[Silvertip]

Re: Greasing wheel bearings

Think about this folks!!!! When you pump anything into a sealed cavity you compress whatever is in that cavity. Pumping excess grease into a hub can and will flip the lip portion of the wheel bearing seal. In a very short distance you will see streaks of grease on the back side of the wheel. If you follow the directions that come with true "Bearing Buddies" you will learn that you pump grease into the hub until the spring loaded disk on which the grease zerk is located just begins to move. Then STOP. That's all you need. The moving disk tells you the hub is now under slight pressure.

If you happen to have the imitation bearing buddies that amount to nothing more than a standard dust cap with a grease zerk attached, those should be trash canned due to the closed nature of the hub. Regardless of the air/grease content, you cannot pump anything into the hub without raising the pressure in proportion to what's already in there. Hence just couple of pumps of the grease gun may flip the seal.

Those systems that have the rubber plug in the cap are ok because there is an escape route for the old grease to come out.

 

[WIMUSKY]

Re: Greasing wheel bearings

I agree w/silvertip. This subject has been discussed in length with various opinions across the board. I've always used BB's on all my trailers. Never had an issue. I like them. As far as if they grease the bearing or not, some say yes, some say no. I tend to think they do. I've gone years w/out repacking bearings without issues. Some will say that's a poor practice. I guess repacking them every year would be the best method since you know what you have and would have peace of mind. I ALWAYS feel the hubs when traveling any distance(longest is usually 3hrs one way) to make sure they're not overheating which would indicate bearing failure. I've never had one fail.

 

[jimbob669]

Re: Greasing wheel bearings

Y'all say just a couple pumps of grease. How often should I do this?

 

[tistore]

Re: Greasing wheel bearings

here is a question i just got the bearing buddies and put them on my trailer...if i pumped too much grease in and it just happen to come out of the back side of the wheel and sprayed all over the trailer and boat and rim..does that mean i have to replace the rear seal on the inner part of my hub? or can i just push the seal back in? never done this before so guess i should go take the rim off my trailer and check it out... ohh just if your wondering yes this did happen i wanted to put sooo much grease in it that i didn't want to worry about the hub and bearings....opps. guess my question is how can i fix the rear of the hub where the grease came out? can i just push a rubber seal back in that it might have pushed out?

 

[Dave Brick]

Re: Greasing wheel bearings

Think about this folks!!!! When you pump anything into a sealed cavity you compress whatever is in that cavity. Pumping excess grease into a hub can and will flip the lip portion of the wheel bearing seal. In a very short distance you will see streaks of grease on the back side of the wheel. If you follow the directions that come with true "Bearing Buddies" you will learn that you pump grease into the hub until the spring loaded disk on which the grease zerk is located just begins to move. Then STOP. That's all you need. The moving disk tells you the hub is now under slight pressure.

If you happen to have the imitation bearing buddies that amount to nothing more than a standard dust cap with a grease zerk attached, those should be trash canned due to the closed nature of the hub. Regardless of the air/grease content, you cannot pump anything into the hub without raising the pressure in proportion to what's already in there. Hence just couple of pumps of the grease gun may flip the seal.

Those systems that have the rubber plug in the cap are ok because there is an escape route for the old grease to come out.

I have "imitation Bearing Buddies", that I picked up at NAPA. They do have a spring-loaded plate, and in addition, have a little teeny indicator hole, (perhaps 1/64"). The instructions say to fill the hub until the plate moves enough for a little speck of grease to come out of the indicator. The indicator hole is well covered by the bra.

These have worked beautifully for me.

 

[Mi duckdown]

Re: Greasing wheel bearings

30 year old trailer with bearing buddies. as Silvertip pointed out don't over grease.