Bearing buddy issues

[ratdude747]

I've been having a few issues with my trailer's bearing buddies (genuine chrome plated) that I installed last spring when I added electric drum brakes to my trailer.

1. The "bra" covers pop off when in use. My assumption is that this is due to brake drum heating which is expanding the air inside the buddy. I've confirmed this by driving with them off, then putting them on when parked or ramp dipping and observing them sucked in as the wheel cools off. Is driving with them off the correct solution?
2. When I pulled my boat out of the water at the end of yesterday's outing, the grease nipple was missing and not in the bra of one of the two units. Thankfully, it was pushing grease out (not sucking it in). Are the nipples replaceable or do I need a new unit? I suspect it fell off when I was towing the boat 1 hour from home to the ramp. I don't recall losing a nipple while topping them off during the offseason.

 

[alldodge]

I'm wondering if the hubs are getting hot, normally the covers don't come off unless pulled off. Do you have a IR temp gun to measure temps.

Could drip a drop or two of water or spit on the hub after a run and before launching boat to see if it sizzles

 

[airshot]

My rubber caps used to come off on ocassion, so I started making a teeny tiny hole with a paper clip right in the middle. When I install them I push on the center to create a little suction on the rubber cap, enough so the center will suck in slightly. I often wondered if heat buildup caused the " bra's" to come off as the center would be bulged out after a trip. With the pinhole, there is no bulging and have not lost another " bra"... Do check your hubs for excess heat. If to hot for your hand to remain on them, you have another issue....warm is fine but never hot !

 

[Mc Tool]

I thought the idea was to remove all the air . I have rubber ones and they do move in and out about ⅜" between start and finish of the trip but not close to popping off

 

[dingbat]

There should be no pressure on the bra.

If you’re popping the bra, the bra is sun damaged and needs replaced or the o-ring on the piston assembly is compromised.

A missing grease fitting would cause the problem as well

 

[Jeff J]

No reason to think a little heat from the sun or heat buildup from being on the road wouldn’t expand the air trapped under the cap and push them out. I had some caps that would push out just from the little bit of compressed air created while pushing them on. The pinhole idea is a good one.

 

[ratdude747]

No reason to think a little heat from the sun or heat buildup from being on the road wouldn’t expand the air trapped under the cap and push them out. I had some caps that would push out just from the little bit of compressed air created while pushing them on. The pinhole idea is a good one.

I know for a fact that happens. Putting the bra covers on warm (not hot!) bearing buddies at the ramp then dipping the trailer at the ramp causes the bra to get pulled in very far. Thus, even with no cover, the heat coming from the hub is enough to warm the air inside the opening of the bearing buddy to the point that it contracts when cooled.

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I can confirm the bearings aren't getting super hot. Just some heat from the brakes doing what brakes do. Nothing to suggest bearing failure. Obviously warmer than a brakeless axle...

As for the grease nipple issue in my original post: is this serviceable or do I need to replace the bearing buddy?

The bras are not obviously sun damaged.

 

[MikeSchinlaub]

By bra, we're talking about the plastic cap right, I find those around our lot all the time, they constantly fall off.

As for the grease fitting, I don't see why you couldn't replace it. They all just thread in right?

 

[Chris1956]

Brakes generate heat. That is their function. Heat expands the grease. That is why automobiles do not have bearing buddies on them.

Try putting less grease on the bearings. Pack 'em as you would a car/truck cone bearing.

 

[Jeff J]

Brakes generate heat. That is their function. Heat expands the grease. That is why automobiles do not have bearing buddies on them.

Try putting less grease on the bearings. Pack 'em as you would a car/truck cone bearing.

While I agree with what you are saying and it is what I do, that kind of defeats the purpose of having a bearing buddy since they constantly push grease in. You either pack the hub full or pump the grease in with a gun. I just don’t use bearing buddies or the other grease gun options. Even Bearing Buddy recommends regular maintenance but, to me anyway, regular bearing maintenance negates the need for Bearing Buddies or other systems.

 

[redneck joe]

do they make a cap for just the zerk? I've often wondered that.

 

[Chris1956]

Steel bearing dust caps with zerks do exist. However, I had a pair, lost one and never found a replacement.

Bearing buddies are better at keeping water out, than std dust caps, and are fine for trailers w/o brakes. However, for trailers that have brakes, and are towed long distances, the bearings will heat up and the grease will expand.

I have bearing buddy equivs on my trailer with disc brakes, however, I do not tow it far, and the brakes are not used much.

 

[MikeSchinlaub]

do they make a cap for just the zerk? I've often wondered that.

You mean a cap to cover just the grease fitting? A vacuum line cap would probably work.

 

[Chris1956]

You mean a cap to cover just the grease fitting? A vacuum line cap would probably work.

I assume he means a standard steel bearing cap with a zerk screwed into it.

 

[airshot]

While I agree with what you are saying and it is what I do, that kind of defeats the purpose of having a bearing buddy since they constantly push grease in. You either pack the hub full or pump the grease in with a gun. I just don’t use bearing buddies or the other grease gun options. Even Bearing Buddy recommends regular maintenance but, to me anyway, regular bearing maintenance negates the need for Bearing Buddies or other systems.

Many don't follow the instructions for using them, thus they have issues and give them a bad name. BB's should extend the time between hand packing and inspection not eliminate it. Been using these for decades, following the instructions, and have had only one issue with a bearing buddy. I only boat in fresh water so that makes a big difference, for those in salt water, you have a whole different set of instructions!!

 

[redneck joe]

You mean a cap to cover just the grease fitting? A vacuum line cap would probably work.

Yeah, that

 

[airshot]

I assume he means a standard steel bearing cap with a zerk screwed into it.

There was a company that made a plastic cap with a zerk fitting some years back. Was not impressed with them nor was others that tried them. Not sure if they are still out there. However, for fresh water use, I highly recommend the Bearing Buddies, but do follow the instructions to get the best performance from them.

 

[Pmt133]

I lost my bearing buddy on my fuel up for the lake trip last year.

I learned that some have a better press fit than others. The replacement needed a sledge to seat fully... thats a problem for future me when I repack them.

 

[ratdude747]

I lost my bearing buddy on my fuel up for the lake trip last year.

I learned that some have a better press fit than others. The replacement needed a sledge to seat fully... thats a problem for future me when I repack them.

Mine took some heavy whacks from a 4lb dead blow to seat. Granted, that was on brand new brake drum/hub units...

The plastic off-brand ones it had when I was gifted the boat were a much lighter fit and leaked grease.

By bra, we're talking about the plastic cap right, I find those around our lot all the time, they constantly fall off.

As for the grease fitting, I don't see why you couldn't replace it. They all just thread in right?

Yes. "Bra" is the term that Bearing Buddy prints on the covers:



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I boat in fresh water. No salt or brackish water!

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To answer my own question, per some google image digging, the nipples have backing nuts. So I'll have to pop mine off to replace the nipple in any case:



It probably came loose for who knows why. If I opt to fix it (rather than replace it), I'll be sure to use some blue or orange threadlocker on it. Maybe do the other side too?