Another bearing question

[Rick Courtright]

Hi,

graygun's quandary about wheel bearings brought out some comments about the "quality" of a lot of our "imported" bearings these days. And reminds me of another experience recently.

A year and a half ago, my trusty ol' '88 Toyota pickup started making a "belt related" kinda noise near the end of a 250 mile run across the desert on a hot summer day. I pulled into a rest area, and figured out it was coming from a belt idler pulley. It wasn't up to "critical" so I slowed down a little and got home just fine. I took off the idler, and the bearing was feeling a bit "dry."

I looked up a new idler, which would be about $150 IF anybody had one. Remember, this is a nearly 30 year old vehicle. But even if it was brand new, that was a ridiculous price. I remembered somebody told me every bearing out there has a number, and a bearing supply house probably has a replacement. I got two new bearings, one for a spare, for about $10. Much better pricewise. Even it they're probably Chinese. They don't say, but the finish on them isn't exactly top notch.

The bearings are sealed. Supposedly, they're ready to go. I pressed out the old one, an NSK which I think is Japan's answer to SKF. It was the factory part and had been spinning along merrily for three decades and about 175,000 miles. I pressed in the new one, put things back together, and drove off. For about 18 months and maybe 12,000 miles, when my noise returned. Rats. I pulled the idler, and the bearing spun freely, but it was easy to tell there was not much lubrication in there. I pulled off the seal, and it was pretty dry. Not a good sign for a bearing which runs in the range of 7500 to 10,000 rpm its whole life--the finest bearing in the universe will fail quickly with insufficient lubrication. Out of curiosity, I pulled a seal from the new one, and it had just a smear of grease on it. So I did what I've done in the past for a "we need a few more miles out of this" situation, and greased up the bearing I'd already been using. I didn't pack it full, but gave it considerably more than it had, even new. Put it back on the truck, and so far, it's quiet.

Now I'm curious, and go visit the SKF site, downloading a fair amount of really technical stuff, and a few words of English that got my attention. It seems many so called "sealed" bearings today come with some grease, but it's a packing grease to prevent corrosion, not a lubricating grease. So the bearing needs to be properly lubed before being put into service (it looks like most smaller ones can have grease added right over the factory stuff, while some bigger industrial sized ones must be washed first.) This is new to me: I've replaced many, many bearings over the years, but they were almost always the "open" style, so I have very little experience with sealed bearings. And in that previous limited experience, they were always "lubed for life" and ready to go from the factory.

Have I been living under a rock? Is grease getting so expensive the mfrs are skimping on it to save a tenth of a cent per unit? Or do the Chinese and some of the other folks who barely know what a wheel is to start with, but are making OUR bearings for us, simply not understand the whole concept of sealed bearing lubrication? Or worse, are the vendors actually spec'ing a "ready to go" bearing, while our little friends are cutting corners on them and haven't been called on it?

I can teach myself to grease sealed bearings before installation easily enough if I must, but I'm still curious. Has shipping sealed bearings "dry" like the older style "open" ones become normal procedure these days?

Rick C

 

[gunzo]

Rick, I must first say that I am a jack of most trades, so take that in stride. Now, with confidence, I am/was a Master Bearing Fitter.
With that said, there are so many variables with bearings that i could go till tomorrow about the proper fit & application of bearings. But, sealed bearings should need no additional lubrication, & yes, they were lubed for their life span. But what is that life span?

The influx of imports, much less copies & counterfeits has complicated the situation to a cluster .....

I don't really have the answer anymore without inspecting each situation in person.

I've not been real active in the automotive scene lately, but starting to avoid the chain stores for related parts. Going back to the local stores here. And... that's a gamble.

 

[powder smoke]

Older cars had bearing that were serviceable and lasted too long! Can't have that!
Now it cost big bucks gotta buy a unite that is the complete hub and rotor.
Public gets screwed again! Saves a bit of assembly time, thing is it is still assembled
anyway and unserviceable! When replacing you must by a whole unite, rip off! ps

 

[Mobuck]

"It seems many so called "sealed" bearings today come with some grease, but it's a packing grease to prevent corrosion, not a lubricating grease. So the bearing needs to be properly lubed before being put into service"

That's a new one one me. We use a LOT of "sealed" bearings on the farm(combine alone must have at least 100 and the baler 40-50). The cheap Chinese bearings don't last well and many of the current bearings have a plastic ball cage but NONE require pre-installation lube. In fact ANY tinkering with the "seal" is an almost certain death sentence for the type of bearings I'm familiar with.

 

[DGW1949]

Some sealed bearings have rubber seals, some have metal seals , some have a rubber coated metal seal. The rubber variety are by far the easiest to service without damaging the seal. Either way though, you can bet the farm that none of them come with an adequate amount of the proper grease. Anyone who doubts that is welcome to look for themselves...just be sure that you know what you're about before attempting to remove/replace those dinky side seals, or else you'll be doing more harm than good if ya damage 'em.

And as Rick C. has attested, the Japs can make a fine bearing. Myself, I believe that NSK is as good a brand of bearing as can be had for automotive use. Still though, if it has rubber seals, I'd dern-sure pack it before putting it into service.

DGW

 

[graygun]

The SKF I bought yesterday from NAPA looks strong and is made in China. NAPA used to sell Timken.

Our other store is a Car Quest and their "better" line is National. I have to go there today to get some Moog (still made in this country) tie rod ends. I'll look at those bearings for comparison to the SKF.

Sealed bearings will always go dry in time. The days of oilable fan motors (etc.) are long gone.

Recently,I heard a mechanic say they have to return about 50% of the parts they buy. They get them from NAPA and Full Service,which are supposed to be higher-level then some of the other ones.

 

[graygun]

I think the sealed ones are supposed to be packed full of grease. We had tons of fans in the flight sim stuff...power supplies and cabinets.

A lot of the Japanese stuff is made in China.

 

[Acorn]

Bad part is many name brand bearings are made in China too. Now are there different qualities?

 

[graygun]

Bad part is many name brand bearings are made in China too. Now are there different qualities?

yes

 

[Rick Courtright]

yes, they were lubed for their life span. But what is that life span?

(Emphasis added)

Hi,

gunzo, thank you for your insights, and right there might be the most important part of this "new learning experience" for me! Perhaps "my" bearing is also used in several applications where it's adequately lubed for a very long service life, yet in the job it's doing for me, its factory lube is woefully inadequate to promote a lifespan similar to the original. It would be fun to be a fly on the wall listening to the arguments between the engineers and the bean counters on some of this stuff. I'll bet you already have some of those stories!

Rick C

 

[Rick Courtright]

Bad part is many name brand bearings are made in China too. Now are there different qualities?

Hi,

My understanding from people who've actually worked with Chinese manufacturing entities is the Chinese CAN provide any level of quality you want. IF you're willing to pay for it. But you must watch 'em like a hawk every second of the day to ensure they don't cut corners on you while you go to get another cup of coffee or hit the little boys room. According to a Chinese client years ago, it's a cultural thing which they don't see that as "cheating" the way we do, and they'll try to beat you out of a buck any time they can, with a clear conscience!

It seems some of our companies here don't understand that, and some do. Add that we too often want Saks Fifth Avenue quality at Wal-Mart prices, and they've got free rein until someone steps in to bring 'em back in line. They'll give us Wally's prices, but we sure won't get Saks quality.

Rick C

 

[gunzo]

yes, they were lubed for their life span. But what is that life span?

(Emphasis added)

Hi,

gunzo, thank you for your insights, and right there might be the most important part of this "new learning experience" for me! Perhaps "my" bearing is also used in several applications where it's adequately lubed for a very long service life, yet in the job it's doing for me, its factory lube is woefully inadequate to promote a lifespan similar to the original. It would be fun to be a fly on the wall listening to the arguments between the engineers and the bean counters on some of this stuff. I'll bet you already have some of those stories!

Rick C

When the bean counters totally win over the engineering dept. a bridge collapses or something similar. If the engineers totally win, the end product would be to expensive to buy. If you put $57 apiece bearings in an application where $7 ones would do, we would all go broke. But, if $7 bearings are used when the best is required, we could go broke or... worse.

When serious about a bearing, you need to be very careful with the "complete" part number, & sometimes additional smaller sets of numbers that show up in another location. This might be quality "class", not just dimensions, load/temp ratings, open, sealed, or how sealed. It can get complicated if it's important. Brand names might even come into play, certifications even.
Or.......... match dimensions, shove in a no name & cross your fingers.

I am aware & agree that the the Chinese can produce quality, but am also aware that they, like many others can & will sell a low grade knock off if people will buy it. Challenging times.

 

[CGDustDevil]

Many bearings are shipped from the manufacturer dry or with preservative unless they're specially ordered for a single type of application. One thing to consider is how broadly a given bearing is used. A bearing that's used across a wide array of applications can't be greased for each application. You found the bearings at a bearing supply which sells to a wide customer base... So you got exactly what I'd suspect you'd get.

Yes - Teach yourself how to clean and properly lube your NEW bearings!

Regards, Pete

 

[Mobuck]

Well guys, we may be talking about different service type bearings. In 1/2 century of dealing with weather-proof ag-type sealed ball bearings, I've NEVER seen one with a seal that wasn't crimped in place. Any of those where any attempt to remove the seal was made ended up ruined. In a few cases, the seal popped out and we continued to run the machine by stopping every 15-20 minutes and squirting some chain lube onto the exposed bearings. This kept the machine going and took only a few seconds but only works when that bearing is accessible.
My baler does have "re-greaseable" ball bearings in a couple of high load locations but those are fed through a hole in the outer race lined up with the grease fitting in the bearing flanges.
My Father-in-law would spend more time than it was worth removing a sealed bearing and dropping it in a can of hot melted grease in an attempt to get some semi-fluid grease past the seals to extend the life of a questionable bearing. I've tried using a syringe to force grease into a sealed ball bearing. Both of those "make do" attempts usually failed miserably.

 

[Bull Barrel]

You guys have never been around Italian moorsickles. Luigi is famous for not lubricating tapered roller bearings.

 

[CGDustDevil]

Well guys, we may be talking about different service type bearings. In 1/2 century of dealing with weather-proof ag-type sealed ball bearings, I've NEVER seen one with a seal that wasn't crimped in place. Any of those where any attempt to remove the seal was made ended up ruined. In a few cases, the seal popped out and we continued to run the machine by stopping every 15-20 minutes and squirting some chain lube onto the exposed bearings. This kept the machine going and took only a few seconds but only works when that bearing is accessible.
My baler does have "re-greaseable" ball bearings in a couple of high load locations but those are fed through a hole in the outer race lined up with the grease fitting in the bearing flanges.
My Father-in-law would spend more time than it was worth removing a sealed bearing and dropping it in a can of hot melted grease in an attempt to get some semi-fluid grease past the seals to extend the life of a questionable bearing. I've tried using a syringe to force grease into a sealed ball bearing. Both of those "make do" attempts usually failed miserably.

Yes - These are different service type bearings for sure! Absolutely not industrial. If the seal is crimped in, then that's another story of course. I have mower decks that use 'sealed' bearings in the blade spindles. They're very easy to pop the seal out of, clean and refresh the grease. I believe the original bearings were, but the replacement bearings one buys today are not.

I have seen the proliferation of these generic 'semi sealed' bearings over the past 25 years or so in automotive and small equipment applications. When I worked in the oil/gas /power-gen field, we'd occasionally substitute these sorts of bearings when they could be found sharing common dimensions with bearings we needed for internal wet applications. We'd simply pop the seals out with a right-angle scribe, clean off the preservative, and we were in business. Same bearing, structurally speaking, and sometimes a fraction of the cost of the "OEM" bearing. In wet applications, the bearings are oil fed, so there's no down side.

If we needed a weatherproof bearing for an external application, obviously that scheme didn't work all that well! Although I have used more than one of these cheapy generics with the removable seal on a temporary basis in order to keep a machine in service while waiting for the proper weatherproof bearing. Sometimes out in the boonies with a customer complaining that he's losing 30K a day with the machine out of order, the cheap 'semi-sealed' bearing makes a lot of sense! If the 'proper' bearing takes a month to get there, no worries. The cheapy will run long enough to get them into a scheduled shutdown, or past a critical production period.

Regards, Pete