Advice wanted on Bearing Repack

bruceb58

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Mar 5, 2006
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I figured someone was going to argue that is why I posted the Timken link. I have seen a few blown or leaking hub seals because of this. Also seen bearing buddies pushed off of hub when they are over filled. You have to all room for expansion.
The Bearing Buddy has a pressure relief that lets some grease out. Bearing Buddys do fall off but that is a caused by vibration with a poor fitting hub. I have bearing buddys on my trailer for my Wellcraft and never have an issue. That trailer has disc brakes and I travel down steep mountain passes in the Sierra Nevada. If you fill the bearing buddy properly and only pump until the cylinder first moves, there is never an issue with a blown seal.

http://www.bearingbuddy.com/install.html
fill the hubs completely

Also, EZ-Lube hubs get completely filled if you inject grease into them and pump until the grease flows out the front cap.
 

bigdee

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Jul 27, 2006
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....as long as they have some means to relieve pressure. Pump BB until piston moves and then the stop.
 

StarTed

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The problem with water entry is air expands when heated and contracts when cooled. Driving down the road then dunking into the cooler water. Any air in the hub greatly increases the odds that water will enter. That's why they should ideally be full and and checking the Bearing Buddies just before launching to make sure there is some pressure against the spring can also help.

I don't know anyone that follows this but I read that many years ago when I installed a pair.
 

bruceb58

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....as long as they have some means to relieve pressure. Pump BB until piston moves and then the stop.
Yep...the problems people have with them are are self inflicted. When you hear about people putting a couple pumps in them every trip, they are the ones that have blown seals. Once they are full, you don't need to ever put more grease in again.
 

Patfromny

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Dec 2, 2012
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So you don't ever check the bearings? That sounds scary. I'm sorry, I don't have them and know nothing about them. I would think you should still open them up each year and inspect them right?.
 

JASinIL2006

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Feb 10, 2012
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Having Bearing Buddies doesn't preclude you from checking the bearings on some interval. For me, BBs extend that interval.
 

bigdee

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Having Bearing Buddies doesn't preclude you from checking the bearings on some interval. For me, BBs extend that interval.

I have one 1989 trailer with BBs that gets used quite often and has never been dis-assembled. Each season I jack up each wheel and feel for excess play, spin wheel and listen for any gritty sounds. I also make sure BB piston has grease pressure on it and add a squirt if it needs it ( which is seldom). I visually inspect seals for leakage....if no leakage it is unlikely water would have gotten into hub. Whenever I removed and re- installed the dust cap or BBs on my other trailers I always smear grease on the mating lips to make them water tight.
 

gm280

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Jun 26, 2011
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Seasonal maintenance is a great idea with BB's or not. But the whole design of BB's is to be used with a little internal pressure. So if you pump the BB up until the center piston just starts to move outward, you then stop. The BB is now full and has internal pressure to keep water from getting in. And as you trailer down the road, additional heat will add to that internal pressure to assist keeping the water from getting into the hub. Even backing a warm hub into the water won't allow water to get in because the initial internal pressure will still be there. If you keep pumping grease in until the center piston pushes out against the stop, then the internal pressure will increase and it has to go somewhere. And guess where that somewhere will be, yes, the read grease seal. JMHO
 
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