old race with just new bearings okay?

[kip22]

Just curious what the consensus is here about replacing just the bearings and not the races if they are in good shape? Several google searches yield answers all over the place. I picked up a couple kits to do my boler. Everything matched up except the inner race was a l168111 and mine was l168110. Don't fit. I hadn't pulled that last race before heading to the parts store so my bad. I ended up just repacking the inner baring and old race and replacing the outers all new. There was nothing wrong with the bearings but I figured for the cost if I'm pulling them out I'll just get new. Wondering if in a year or two whe I repack again if It's advisable to use the new bearings with the old race if they look good?




Hopefully this helps someone else. Bearings and race are matched to each other but not necessarily to the hub.





cheers

[floyd]

Clean and inspect bearings when doing a hand repack.
It is at least as risky to replace a known good bearing with a new one.
My advice is to not replace good bearings which exhibits no wear.


Races are matched to their bearings, and it generally best to replace them as a set.

Use good judgement when assessing the bearings and races.
If a bearing is worn or broken then the odds are so is the race.
If you are just replacing good bearings for fun then the odds are it won't matter either way.

[redbarron55]

Back when I worked on light airplanes some inspectors seemed to find bad wheel bearings at every annual inspection. I must have been doing my inspections wrong as I almost never found a bad one.
Of course I did not collect the money for new bearings and the labor to replace, either.
I suspect a lot of those "bad" bearings were gundecked and not replaced, just charged for.
I suspect that there a lot of good bearings replaced and perhaps more problems installed while doing it as well.

[kip22]

Thx for the advice. I'll leave well enough alone for now. I've had the boler about 9 years and it came with those bearings so I figured I should just do it this time around.


I had a friend a couple years ago have a failed bearing on a road trip resulting in a tow job and he had them repacked at the rv place that spring. Supposedly they were in good shape and did not need to be replaced. Coulda been a **** job packing grease or no grease at all or they could have failed even though they looked good. There must be some kind of time/distance where you just replace on spec?

[CharlesinGA]

Next time you pull the hubs replace the bearings and races with new Timkens and good synthetic Moly grease and be done with it.

I posted this bearing chart elsewhere in this forum, but here it is.



If your bearing combinations equal one of the sets I have listed, you will be money ahead. I buy them from Summit Racing, about $11 for a bearing/race set and about $8 for a seal. They can be found on Amazon but if not from a reputable firm I would be careful as there is a lot of Timken counterfeits running around.


I suspect that your parts store bearings all say China on them and they are IMHO not worth the metal they are made out of.

Timken, Toyo Koyo, possibly SKF, thats about it nowdays for good ones.

Bearings go bad from sitting. I started out working on light aircraft, and the ones that sat alot always had bad bearings and races at Annual time. Moisture possibly, and electrical current passing thru the bearings, dunno.

I worked for an airline for 31 years, changed a lot of wheel/tire assemblies. During wheel rework the bearings went into a degreaser and then were inspected. Not too often were they rejected. For many years we did not use a torque wrench on the axle nut, never had any bearing problems. Finally the Feds got weird and we had to buy torque wrenches and station them everywhere in the company that wheels were kept for spares. On one model aircraft we suddenly started having bearing failures left and right. Then someone noticed that on the same model aircraft that we had acquired from another airline, there were no bearing failures. Then it was discovered that the maintenance manuals for those other aircraft had a lower torque spec for the axle nut than our aircraft had. Torque spec was changed fleetwide and problem went away. Bearings don't mind being a little loose, but will fail quickly if overtightened.

All of my factory car manuals for front wheel bearings, 1967 Ford, 1967 Chevy, 1970 Ford, even a 2006 Mercedes Sprinter, all call for about .005" endplay on the hubs when the axle nut is properly set.

The axle nut on a lot of trailer axles, up to at least 6k lb or so, is 3/4-14 thread. If you tighten up the nut real tight to seat the bearing, loosen it, and resnug it, depending on where you are in relation to the cotter pin hole and the slot. backing it off might be too much.

For every full turn of that nut, you move the nut in or out, 0.0714", with a standard 6 slot nut backing it off one slot is about 0.012". So if you are close to the next hole and need to back the nut up, you will end up backing it up .008" or .010" so you are outside that desired .005" max end play that everyone, including Timken, says is preferred. What you need is nuts with 12 slots, then backing up one slot will be less than .006" and you will be fine.



If you do not have a "jiffy lube" axle and have one with castle nuts on it, if they are not the 12 slot nuts, you should consider replacing them the next time you have them removed. Dexter sells them under the same part number the older six slot nuts were sold under, so you need to make sure of what you are ordering. The Dexter number is 006-176-00 Which is sometimes expressed without the dashes. This nut allows much more accurate setting of end play of the bearings than a six slot nut will.


Charles

[Raspy]

You could look at it this way:

If after a close inspection you decided that there was nothing wrong with the bearings, there is no reason to replace them.

If you find a problem with the bearings, it means the races have been compromised too.

So, if there is nothing wrong wit the bearings, don't replace them. If there is something wrong with them, replace the races and the bearings.

[CharlesinGA]

Correction, past edit time, in my post above, I got the axle nut size wrong, its 1"-14 NOT 3/4-14. Not sure how I did that.

Charles

[redbarron55]

Again in another life working on NASCAR Grand National cars for qualifying. We set them up loose and used a grease about the consistency of Vaseline for qualifying.
As the Crew Chief said. It's only got to last 3 laps!.
That was a 3500 lb car traveling over 200 mph on the high banks of Daytona.
I don't recall losing any bearings doing that.
If the bearings are not submerged like in a boat trailer they should last a long time as long as they are adjusted correctly.
In industrial applications we often use vibration sensors along with thermal sensors. These let us know the condition of the bearing and alignment of the system. We can see the temps go up after adding grease to a motor, for example.
In my case I check the temperature of the hubs after a few miles and at each stop to keep a check on things. The hubs (as long as you haven't used the brakes heavily - I check by slowing down over a distance like pulling into a rest stop. )
The hubs should be only slightly above ambient.
The best predictor of trouble free operation is the time spent before. If it worked before and it is running cool it is likely to keep doing that.

[Darwin Maring]

When you follow directions you will have a higher degree of success. Bearing and race come together in a package. Do it right and you should have no regrets later.

[Mike_L]

I usually replace both bearing and race. The race may not have visual damage but I'm not always sure and for the minimal cost of replacement, why take the chance of a road failure.

[ehoepner]

A non contact Temperature reading tool is great to have. After traveling a couple hours and you stop read the Temperature on each wheel hub. If it is over 160 degrees farenheit its time to address a bearing issue.

Another way to check the bearings is to jack up the wheel and spin the wheel. If you hear some grinding it's time for a new set of bearings.

[John McDonald]

Originally Posted by ehoepner

A non contact Temperature reading tool is great to have. After traveling a couple hours and you stop read the Temperature on each wheel hub. If it is over 160 degrees farenheit its time to address a bearing issue.

Another way to check the bearings is to jack up the wheel and spin the wheel. If you hear some grinding it's time for a new set of bearings.

And check the brakes. Could be too tight.

[Herb Sutton]

A failure on the road could ruin a trip, is it worth the risk?

If a bearing seizes and galls the axle it becomes major.

[Raspy]

Originally Posted by ehoepner

A non contact Temperature reading tool is great to have. After traveling a couple hours and you stop read the Temperature on each wheel hub. If it is over 160 degrees farenheit its time to address a bearing issue.

No thermometer is needed and no specific temperature defines the difference between fine and problem. The simplest way is to simply touch each hub at each gas stop. If one is too hot to hold your fingers on, there is some kind of problem. They should all be about the same temp and not much warmer than ambient temp.

I touch them at every gas stop with a simple walk around while filling up. I touch the hubs and each tire on my way around. I removed the decorative hub caps to give access to the hubs.