Well, I see this subject has revived again! OK, we have finished another season, our 5 boats, portable jump, dock trailers have been launched another 100 times each, and still no bearing failures - and none have been repacked - in as many as 25 years, using Bearing Buddies and whatever brand of grease is in the gun at the time!
Steelhead, how would the water get in if the bearing buddy is pumped up and has positive pressure inside?? Now, our big ski jump is in the water for 5 months straight with the wheels on it and.....
Hitting cold water causes them to "suck the water in" Even if there is positive pressure inside? Now, I have driven into cold puddles and backed into cold water with hot tires all my life and never had water sucked inside any of my tires!! Of course not, they have positive pressure in them!!
Much like a bearing with Bearing Buddies!
Lets assume there is a pinhole leak, and grease coming out through it. The water could go upstream?? The bearing buddy would soon be flat???
Now, in salt water I would want to watch the center piston carefully and make sure that it remains free so the spring can keep positive pressure on the grease!
That is why I recommend avoiding all other brands (unless you can determine that they are all good quality stainless steel, etc ... and probably leave the outside a little greasy also for protection. The plastic "red eye" brand that we put on a tandem axle trailer 10 years ago had a 75 percent fail (jammed up) rate within one year in our service. That of course caused some of the bearings to begin to fail - we caught them well before catastrophe.
And, of course a Bearing Buddy will do you little good if the rear
seal has failed, or if you let the pressure piston go flat for any reason. Generally, we use them all summer long without having to refill them - but we do check them before every road trip - often 800 miles on a weekend.
Incidentally, the 1984 Shorelander trailer that has been in continuous use without repacking the bearings has worn out 3 sets of tires during this time!!
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