Ok, so we loaded up and headed out for a day on the lake Saturday. "clunk, grind, clunk, grind" On inspection, the bearing buddy cap is gone, and the outer bearing is wobbling on the spindle. After removal, the inner bearing and seal are in pieces. The other side was on the way out too, races all pitted. Plenty of grease left, and the bearings were replaced early this spring.

What's going on?

Your bearing failed.

Usually due to incorrect pre-load during assembly, but on a boat trailer, and with the cap gone, you probably got water in there. Oar, someone introduced dirt during repacking. Double-oar the inner seal was installed backwards.

But bottom line, "somebody" wasn't paying attention is the most likely reason for the failure.

As an aside, I ALWAYS stop after a few miles and feel the temperature of the hubs. Warm/hot = "Al, ya better take a look at this one..."

I'm sure the cap blew off when it failed. It's possible the inner seal was backwards. We didn't do the work, but a very good semi owner and mechanic did it.

Even if there was water in there, shouldn't the full load of grease still protect it?

In my limited experience, all based on salt/brackish water, nothing but a dry (with grease, but no water) bearing survives long. Most of my boat-owning friends regard wheel bearings as an annual expense on their trailers.

Drove 100km with a small sailboat on a trailer with a good friend a few years back. It started growling halfway to our sailing venue. On the way back, the wheel was visibly moving 1/2" or better. It's surprising how quickly they FAIL after they begin to fail.

J

Nope.

LOTS of reasons for those bearings to fail, but they rarely do on their own. There's always a cause, and so soon after being serviced, it's usually the last guy who touched 'em's fault.

Ok, thanks guys. Getting them redone as we speak. I guess that's going on the seasonal check list. I can't stand TB whining when he can't go fishin'.

Repack every 4-5 years for me. But like I said, I check 'em for heat OFTEN. (I have 5 to keep after...)

90% of the grease in there does nothing....
the grease packed in the bearings does all the work.

water and/or a couple pieces of 'grit' and you're done.

Some people take bearings right out of the box and install,
I clean 'em first, then pack well.

Packing is the secret! gotta be done right.

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