Wheel Bearing Question

Earlier this spring I replaced the bearings, races and rear seals on my boat trailer. Been using all summer but, all local trips. Yesterday I went to a lake that was about a 2 hour drive away. Stopped half way for a cup of joe and something inside me told me to check the wheel bearings. One of the hubs was warm to the touch. Not hot, just warm. Drove the 40 miles to the boat landing and felt it when we got there. A little warmer but still only warm, not hot. Made the trip home and stopped every 30-45 miles on my 2 hour drive back home and continued monitoring the hub. By the time I got home the hub was hot. Not so hot that I couldn’t keep my hand on it, but more than warm. The only thing I have done so far is jack up the trailer and try to wiggle the tire. No play in the tire at all. A guy at work this morning is wondering if I maybe tightened the hub to tight after replacing the bearings?

Does that seem right? Any other suggestions? Second question, will I need to replace the bearing? How will I know if they got too hot? Color? etc.? Any suggestions would be helpful!

Thanks!

Gerty

I guess my question would be, what procedure did you use when “setting” the bearings? Using the word “tighten” probably means that you set them too tight. For as cheap as bearings, races & seals are, I’d install a fresh set.

https://www.boatingmag.com/maintaining-boat-trailer-wheel-bearings/

HRG

If the hub is hot and no play in the wheel either the bearing was tightened down to much or not enough grease was forced into the bearings. I’d pop the cup and pull the bearings and look at the race and bearings after wiping them off. If they appear a deep blue to purple color they’ve gotten to hot. I suspect over-tightening them.

When I do bearings I set them by spinning the hub un each direction after finger tightening the nut. Then I’ll tighten the nut no more than about 1/8 of a turn to get the key in place. If I have to go more than 1/8 turn to do this I back off to the first keyway to insert the key.

It was really hot yesterday!
Running 10-15° over ambient isn’t a concern. Highway I’ll bet was quite warm.

I have a utility trainer where one runs a little warmer than the other. Your like me… checking it often on a trip rather than be caught with trouble! Probably just a little more snug than the other.

I would check on your next trip before changing anything, when it is a little cooler. I check mine every trip that’s at least 20 minutes.

When I tightened them, I tightened and then backed off to the next spot the key would fit through. After I took it on my first trip I jacked it up when I got home just to check. Both wheels seemed to have a slight amount of wiggle. Snugged them both up until no play in the wheel and left it at that. One was maybe just right then, and one probably just to tight. I will pull it apart this weekend and see what they look like.

Thanks fellas!

FishBlood&RiverMud wrote:

It was really hot yesterday!
Running 10-15° over ambient isn’t a concern. Highway I’ll bet was quite warm.

I have a utility trainer where one runs a little warmer than the other. Your like me… checking it often on a trip rather than be caught with trouble! Probably just a little more snug than the other.

I would check on your next trip before changing anything, when it is a little cooler. I check mine every trip that’s at least 20 minutes.

The other one was not even noticeably warm. Even as hot as it was yesterday. I’m sure it is just a tad too tight. Only take a few minutes to check it out make sure it’s good to go. It made it home on the 2 hour drive. Not sure it would have made it 3!

They will get hot enough that you can’t hold your hand on them, especially on a sunny day. In order for them to fail the oil film has to be interrupted, the grease/oil is generally good to about 375-400 degrees. Normally when I grab the wheel I can move it just a bit and get a slight clunk/tick from the rocking. If one is running hotter than the other best to pull it apart and check it out and redo it. Was there a reason you replaced the bearings? Bearings with proper maintenance should last the life of the trailer.

A tiny little bit of wiggle isn’t necessarily a bad thing. I would also say the hub was over-tightened. But if you could leave your hand on the hub, I wouldn’t worry too much as I doubt it was overheated. Maybe check pre-load on the bearing, ensure the grease is at an acceptable level and keep it rolling.

You never indicated if you have trailer brakes or not. If so, it could be a brake shoe or pad dragging, and causing the heat.

HRG

onestout wrote:

They will get hot enough that you can’t hold your hand on them, especially on a sunny day. In order for them to fail the oil film has to be interrupted, the grease/oil is generally good to about 375-400 degrees. Normally when I grab the wheel I can move it just a bit and get a slight clunk/tick from the rocking. If one is running hotter than the other best to pull it apart and check it out and redo it. Was there a reason you replaced the bearings? Bearings with proper maintenance should last the life of the trailer.

Never ever had hubs get so warm that you can’t hold your hand on them and they are still OK. As mentioned, the other side was perfectly cool (air temp). Replaced due to rear seal failure/wrong size. Found out the hard way that they make two rear seals with the same outside diameter (fit hub perfect) but different inside diameter (let water in)

Hot Runr Guy wrote:

You never indicated if you have trailer brakes or not. If so, it could be a brake shoe or pad dragging, and causing the heat.

HRG

HRG – no brakes. Good thought though.

When we do the 10 hour run to Erie if the sun is out on a warm day I can barely touch my hubs, when we run at night they will be cool. The bearings are 20 years old and are still like new. As far as the seal, yeah, my trailer has that odd size as well, it sucks, you can’t get the seal for a normal hub size. I think it is ez-loader that had that great idea. I had to replace a seal this spring as well.

No one asked about the grease packing, are they packed? After the initial packing have you repacked the grease? Some air/voids could have been in the grease and after the grease heated up and moved around left a low grease in the hubs?

I live in Blaine and drove to Elk River to Cub to stop so my wife could get some supplies, while waiting, I checked and felt my hubs also and they were fine. At the stop light in Zimmerman 10 miles up the road someone road up to me and told me my wheel on my boat was smoking. Pulled into the Dairy Queen there and the hub was red hot and the bearings were gone. why did it not burn up on the 25 mile trip from home to Cub?

Probably not relevant but I will share a personal bearing story anyway. I was about to go on an 800 mile road trip with the boat and had Les Schwab check and repack my bearing. 100 miles into my trip the bearing buddy was smoking hot at a rest stop. I called the nearest Les Schwab which was about another 50 miles down the road which we limped into. Upon close inspection, the tech put too long of a cotter pin in and/or didn’t bend it over enough so it was rubbing a groove on the inside of the bearing buddy. They put the correct length cotter pin in and we were good the rest of the trip.

bigcrappie wrote:

No one asked about the grease packing, are they packed? After the initial packing have you repacked the grease? Some air/voids could have been in the grease and after the grease heated up and moved around left a low grease in the hubs?

If this were the case, there should have been a sign that the spring cap on the bearing buddy would have sunken in.

Had bearings changed before trip to Erie. Stopped after first 70 miles to meet friends going with us from another town. While waiting for them found one hub a lot warmer than the other similar to what you descibed. Jacked it up on the spot and found that the wheel didn’t spin as free as it should have by hand. Loosened it up to spin more freely as it should and went on our way. Never had anymore trouble with it and ran those bearings a few years till sold the boat and trailer.