Wheel bearings
Submitted by collin g wood on Sat, 2016-02-13 13:48
What would the normal operating temp of boat trailer bearing be? Replaced mine the other day, towed the boat to Mandurah and they got to 42 deg, checked them again at home and they were 51 deg, checked with a fluke temp gun.
stevebw23
Posts: 155
Date Joined: 12/11/11
im no mechanic but that
im no mechanic but that would be about as hot as the road on a sunny day so in my opinion thats not too bad for wheel bearings
Symes Plumbing & Gas. No job too small, servicing all northern suburbs
Taffy
Posts: 183
Date Joined: 04/11/10
I would have
I would have thought that them temps would be Pretty good, seeing Timken state on there Bearings not to operate Above 150 Deg c
Scotte
Posts: 1142
Date Joined: 07/12/06
Dont forget if you have
Dont forget if you have brakes you'll get heat radiate from the rotor thru the hub and into the bearings etc..
opsrey
Posts: 1200
Date Joined: 05/10/07
Likely on the hot end of OK.
wheel bearing temperatures can be from bearly Luke warm to slightly hot to touch (fingers on hub where bearing is with a little pressure should not hurt enough to need removing from hub but heat can be readily felt)
The issue normally arises from the bearing retaining nut being done up tight, wheel rotated a few times (should be a little hard to rotate) then gently back retaining nut off until fingers can operate nut. Do the nut up finger tight, and look for the split pin hole. Sometimes the pin hole is further away than ideal but you must tighten the nut to line up the pin hole and castle nut, sometimes the pin hole alignment can be a little more than you would like. A little tighter than finger tight is good, and a that extra little bit of turn adds up to a good more pre load. Which is where the temperature comes from.
If the hub temperature worries you simply take the dust cover off the hub, remove the split pin, carefully back off the castle nut ever so slightly to align the nut and hole at the next spot in the undo direction. Reinsert the pin and flare. NOW jack wheel off ground and ensure there is NO free play (rattling movement) of the wheel. None at all. If all that's OK replace the dust cover and check temperatures on next run.
I had the lads at work machine me some castle nut washers. I got them to make one at 150% thick and one at 175% thick. So now I can change washers when I feel the pin hole is too far to tighten the castle nut. The differen thickness means the hole can be organised to be closer turning than with the standard washer distance.
My OCD with bearing temperatures is moderating, I like them to be only just detectably warm. Remember a cold bearing will be a loose bearing in a thousand km or so. A very warm, but not hot, bearing will be a loose bearing after many thousands of km.
A loose bearing (free play) is bad. A hot bearing hub which you can't hold your finger on for any time lenght is also bad. No grease is bad. Water in grease is bad (grease will be strange grey milk colour).
I hope this helps
holth
Posts: 812
Date Joined: 09/10/06
Does your trailer have
Does your trailer have brakes. How your brakes are set on a mechanical setup can make a difference. If your brakes are set tight on the hitch the heat will radiate through the hub more that a brake set looser as they wont be activating harder on the disc on light breaking. Reason l say this is l redid my bearings awhile ago and had the brakes set on the loose side. My hubs where never hot to touch. I then tightened my brake cable up and now the hubs are getting alot hotter. Mind you it was a 40c day.
At work we set trsiler brakes so when you pull the lever at the hitch you can get your pointer finger between it.
Regarding how tight to set the castle nut, some times you can have the nut really tight and you still get good free spin. No trailers the same and the castle nut some times juat doesnt match up to the perfect position.
Auslobster
Posts: 1901
Date Joined: 03/05/08
Wow!
Excellent explanation, opsrey! Can certainly see your OCD! Some valuable info there, and great idea, using different washer thicknesses to get the holes to line up at the optimal tension...
Vinesh87
Posts: 2751
Date Joined: 02/04/11
My hubs use to easily run at
My hubs use to easily run at 80c with my Trophy (2.7T +) under heavy braking around town. Tow them a good distance they were probably about 65-70c. Hot to touch but you could keep your hand on it. Never had a issue in 2 years. Just note even low tyre pressure and the heat disipated from the wheel could increase those temps. but they sound pretty good to me !
I have not tested my new hubs on the preston (3.2t+) but they are always warm to touch. but are only ever hot if i incease my braking to +1,2 or 3V which i have no need to do but did by accident one day!
Another question for the brains trust, does type of grease have any effect on hub temp. E.g i have a small box trailer call it 400kgs, never had a bearing issue, never even got warm( and they were not loosy goosy)Now i have replaced the bearings and repacked with HTB which i have never used before and they run fairly warm all of the time ? Ideas?
opsrey
Posts: 1200
Date Joined: 05/10/07
I'm no brain trust
you do mention you have changed the grease. Therefore you have retention end the castle nut.
It is important to know the preset tension on a used wheel bearing is less than a new bearing.
So a trip to Exmouth and back followed by a check and regrese will require less pre load than a new set of bearings. Soooo, I'd try backing off the nut to next undone hole position and checking for any free play.
This is why I got the lads to machine up some washers for me. Different castle nuts would be my next idea.
Vinesh87
Posts: 2751
Date Joined: 02/04/11
Nah def not too tight, back
Nah def not too tight, back it off one more and its lose. But i see your point about different washers. Will try back it off a bit less with some washers.
Never had a issue with any trailers before its its not even that hot was just wondering the effects of different thickness and heat rated greases.
Cheers
Vinnie
ranmar850
Posts: 2702
Date Joined: 12/08/12
Ospey has covered it well, but there is another trick
Can't get the right tension on your bearings, as the castellations seem to be in the wrong place.? Try this little trick, works for me. Not all castellated nuts are identical re the relationship between the starting ramp of the thread and the castellation slots.When this happens to you next, grab a spare nut castellated axle nut from your toolbox and try that. Every chance it will seat in the right position to tension the bearing correctly. Then, if the bearing on the other side has the same problem, try the first one you took off on it--chances are it will be a good fit. Might sound silly, but it can work, has for me. Alternately, just get a thin washer of the right size and use that as a shim over the normal washer, this will also work.
opsrey
Posts: 1200
Date Joined: 05/10/07
Great idea.
thats a very good idea. My obsession has one more element to it
Ian S
Posts: 71
Date Joined: 20/01/14
Good quality axles
Have two cotter pin holes, which allow you to move your nut 1/12 of a turn at a time.
Unfortunately they are not as common as they used to be.
I think that I've expressed this opinion on here before but this is how I do it, "if you've got play its too loose, no play at finger tight is perfect, its better to be a little loose than too tight".
collin g wood
Posts: 313
Date Joined: 18/04/11
.
Wow, more info than I expected, all good info and much appreciated, pretty sure I have the right tension on the nuts and can quite easily leave my finger on the hub at those temps, I was worried about the brakes being over adjusted so backed them off just enough so the hand lever will stop the trailer from moving at about half its movement range, the bearings I put in were $20 a set from a boat shop, are there different quality bearing or are they all much for muchness? I'm not stressed about the running temp, was more interested to know others thoughts.
opsrey
Posts: 1200
Date Joined: 05/10/07
German and Japanese bearings top shelf
chinese are often second best.
its all about metal quality and tolerances.
streaker boy
Posts: 527
Date Joined: 23/05/09
What brand of bearings do u
What brand of bearings do u think are best ?
cruzy111
Posts: 274
Date Joined: 08/10/13
Is there anyone else on here
Is there anyone else on here that doesnt trust anyone else to do there bearings. All my bad experiences with trailers over the years have been when someone else has done the bearings. My latest laugh was when a friends wheel nearly fell off when he pulled into the cvan park. So ok didnt have a new bearing and put on an old bearing to get him out of trouble. It was in average condition at best. Last day of his trip took the boat in to get bearings replaced. Got the bill no bearings on invoice? Nah mate just repacked your bearings nothing wrong with them. HaHa. And yes Chinese bearings are nearly always rubbish. I would like to know what other people use ? Even name brand bearings seem to have different countries of manufacture now.
streaker boy
Posts: 527
Date Joined: 23/05/09
I use timkens which think
I use timkens which think made in the states
Ian S
Posts: 71
Date Joined: 20/01/14
Timken Bearings
I've had Timkin that were made in China and they seem to be OK but I've had chinese made ball bearings that haven't performed very well, not all of them, but out of 6 that I replaced last year 4* 1 inch flangettes have been very good a 1 1/2 flangette good and but a 1 1/4 that only went 70 hours when I would have expected a least 600 hours going on previous experience.
Moking
Posts: 1252
Date Joined: 30/05/12
Just a heads up on a long
Just a heads up on a long hot trip back last week when it was 43 degree's.
I replaced both wheel bearings before leaving,as I normally do on long trips- all good.
But what did happen,and it could of been because of the extremely hot road condition,one tyre valve stem failed. These have been on the trailer for years,and it's something I would normally not think of checking.
Both were badly perished and cracked on the stem. Many years of in/out salt water and in the sun...
Replaced both when got back.
My Dad taught me how to Fish-Thanks Dad.(RIP)
Tim
Posts: 2497
Date Joined: 26/09/06
Stem
Sulo
Posts: 256
Date Joined: 13/08/11
Any bearing is fine as long
Any bearing is fine as long as it is Japanese made.
Valve stems going are not as uncommon as you would thinkk, never had one go on a car but had a couple on boat trailers. As Moking said salt and sun must deteriorate them. I heard mine go like a gunshot knew something was up pulled over in time before the tyre got shredded. For the inconvenience probably worth getting replaced whenever they sart looking suspect.