Bearings and Seals

[centennialman]

Yesterday, My Dad and I repacked the bearings. I have a new (2year old) Henschen axle.

On the curbside the seal had a spring and on the streetside the seal had a smaller rubber piece with no spring.

The axle was installed by a dealer (not in Denver) because I was recuperating from a knee replacement at the time.

Has anyone come across this situation before? I wonder if the seals are installed by the dealer at the time the axle is put on the trailer, or, if they came that way with the axle.

I could not find any seals that would match at NAPA. We carefully checked them out and there weren't any nicks, dents, scratches etc....and we had to re-use them. I am just curious as to why one had a spring and the other was a completely different type?

[overlander63]

Originally Posted by centennialman

Yesterday, My Dad and I repacked the bearings. I have a new (2year old) Henschen axle.

One the curbside the seal had a spring and on the streetside the seal had a smaller rubber piece with no spring.

The axle was installed by a dealer (not in Denver) because I was recuperating from a knee replacement at the time.

Has anyone come across this situation before? I wonder if the seals are installed by the dealer at the time the axle is put on the trailer, or, if they came that way with the axle.

I could not find any seals that would match at NAPA. We carefully checked them out and there weren't any nicks, dents, scratches etc....and we had to re-use them. I am just curious as to why one had a spring and the other was a completely different type?

It could be the installing shop damaged one of the seals supplied, and got a replacement.

[centennialman]

Originally Posted by overlander63

It could be the installing shop damaged one of the seals supplied, and got a replacement.

Thanks Terry! That makes sense. I am going to hunt down the replacement seals and have some on hand for next time.

[HowieE]

If the axles came from Henschin as a Complete axle the seals were installed at the factory. If you bought just the axle and had your backer plates and hubs reinstalled on the new axles then the shop that did the job probably had 2 different seals in stock.

Most people suggest the spring backed seals be used. Unless you are going through water frequently it is not a big thing considering you will remove the seals long before they will fail because of the frequency that one has to check the brake magnets.

Not sure how you removed the seal without damaging. Normally I have to drive them out with a hammer and damage is a given. It is a general rule to replace the seals every time you remove the hubs to repack or replace the bearings.

A side question.

You say your axles are 2 years old. Was there any level of orange coloring to the grease or the spindle when you removed the hubs? I ask this because I replaced my axles 3 years ago and the factor supplied grease had discolored, Ashland Oil.

[centennialman]

Originally Posted by HowieE

If the axles came from Henschin as a Complete axle the seals were installed at the factory. If you bought just the axle and had your backer plates and hubs reinstalled on the new axles then the shop that did the job probably had 2 different seals in stock.

Most people suggest the spring backed seals be used. Unless you are going through water frequently it is not a big thing considering you will remove the seals long before they will fail because of the frequency that one has to check the brake magnets.

Not sure how you removed the seal without damaging. Normally I have to drive them out with a hammer and damage is a given. It is a general rule to replace the seals every time you remove the hubs to repack or replace the bearings.

A side question.

You say your axles are 2 years old. Was there any level of orange coloring to the grease or the spindle when you removed the hubs? I ask this because I replaced my axles 3 years ago and the factor supplied grease had discolored, Ashland Oil.

We carefully removed the seals by gently running an open end wrench around the circumference underneath the rubber. They easily "popped" out. There was no force involved and it did not damage them at all. I didn't have any choice other than to re-use the seals I had. We carefully inspected them (even with a magnifying glass) and they were fine. I will seek out some of the ones with springs to have on hand for next time.

The color of the grease was still red, everywhere, including the spindle. It looked as if the last packing had just been done. When I bought the new axle, I had the brakes, drums....everything replaced all at once.

[safari62]

Steve
Did you notice the make and country of origin of the bearings and seals after removing and cleaning the parts?

I was more than surprised to find Chinese bearings in my almost new replacement axle. They did not look good and the seals had let dirt and brake dust in so out they went and replaced by Timken USA made bearings and seals.

I did try the NAPA route and than made the long drive to the closest Airstream dealer. If it is not too late I can dig out the serial numbers.

Let me know.
gary

[tkowalyk]

I have a 2006 Safari -- with neverlube bearings. The maintenance recommends lubing every 12 months -- but I have read that this is not necessary -- and 3 - 5 years is recommended?

Any advice or opinions welcome.

[centennialman]

Originally Posted by safari62

Steve
Did you notice the make and country of origin of the bearings and seals after removing and cleaning the parts?

I was more than surprised to find Chinese bearings in my almost new replacement axle. They did not look good and the seals had let dirt and brake dust in so out they went and replaced by Timken USA made bearings and seals.

I did try the NAPA route and than made the long drive to the closest Airstream dealer. If it is not too late I can dig out the serial numbers.

Let me know.
gary

Gary,

The bearings were made in China. Everything was fine with mine, no dirt etc.... and the seals were fine. I am, however, going to hunt down some American made bearings and the right seals.

Thanks!

[HowieE]

This is the reason I asked about the color of the grease. This is what I found when I opened my 2 year old axles. Chinese bearing and seals but Ashland grease.

The reason I opened the axles at that time was the complete lose of ALL brakes. The reason for the brake failure was the Chinese magnets. When they ware the dust forms a cement in the center hole and afixes the magnet to the arm. Once the magnets ware to the limit of the cemented arm the magnets no longer contacted the armature and I had no brakes.

[HowieE]

Sorry pictures were too big.

[Gene]

Some like the seals with springs better, but if you replace the seals frequently, I doubt it matters. Airstream OEM seals do not have springs and the best ones (much superior to the OEM ones) Inland sells do not either.

Airstream recommends repacking the bearings every 6 months or 10,000 miles, whichever comes first. I doubt many people do it every 6 months and a lot don't do it every year. Since trailers sit a lot, water can collect in the hub and compromise the grease. If they are pulled a lot year 'round, the water would probably evaporate, but few people do so much driving.

Getting the inner seal out without damaging it did not seem that difficult to me. I used a 1" dowel about 8" long and tapped the dowel against the seal using a rubber mallet, working my way around it to push it out evenly, hitting it a little harder after a few go 'rounds until it fell out. The wood dowel is easier on the seal and working around it prevents bending it. Whether you replace them is up to you.

Check the bearings and races carefully for scratches, burning. All these parts are cheap (the best seals are not) although it adds up for 2 axles. I have read magnets last about 20,000 miles. At that point you can buy a new backing plate with everything new including shoes cheaper than buying shoes, springs and magnets. Seals, races and bearings are separate. You can also get a backing plate with self adjusting brakes. Since the OEM plate is not self adjusting, adjusting brakes frequently is important.

Neverlube bearings include the danger of packing too much grease into the hub since you can't see what's in there and leaving no air space in the hub to allow the grease to cool. You still have to check the seals and the rest of the innards annually, so I'm not sure you gain anything with them.

When I saw how much a dealer wanted to repack the bearings and adjust the brakes ($160 an axle) and that didn't include any new parts except maybe the seals, I decided to do it myself. It's a tedious and dirty job, but I sure saved a lot of money. I got a bearing packer and that saves a lot of time. Cleaning the old grease out takes a lot of time. I first blew out as much grease as possible with a compressor, then washed them in a solvent, let the solvent evaporate, and repacked them.

Gene

[centennialman]

I wiped as much grease as I could off the bearings and then soaked them in the solvent and cleaned them with a brush. Then, I blew them out with a compressor and soaked and cleaned them again. The final step was once more with the compressor and everything was clean.

[AirsDream]

Most "experts" will tell you never to use a compressor to blow grease or solvent out of a bearing ... risk is that it will spin a race or roller (or ball) up to a very high speed (dry) and score / gall it. I'm not sure whether those experts are right, but it seems to be a bit of received wisdom. I personally have occasionally ignored those experts, but a) only using pretty low air pressure, while b) physically holding everything tight in an absorbent rag so that nothing can move. No bearing failures have resulted, but it's probably tempting the gods. As always, YMMV.

[Minnie's Mate]

I called Jackson Center and got the model number for the grease seals for my Airstream. I ordered them from Out-of-Doors Mart and got the blue ones that "a well known" Airstream repair shop sells for half that shop's price. I took them to my local trailer mechanic and had their mechanic use them. I also ordered an extra set for next spring when it's time to do it again.

[Wingeezer]

Gene,

Just curious as I have not done this yet on our trailer....... when you tap the seal out with a dowel or similar, are you not actually tapping on the inner bearing, which in turn hits the seal and knocks it out? End result of course the same.

With other trailers I have worked on, it has usually bee my practice to put in new seals every time I inspect the bearings, and so I just drive a screwdriver in between the metal housing of the seal and the hub and pry the seal out. Quick and dirty!

Like you I am a firm believer in doing my own work when it comes to repacking bearings. I'm sure there are many good RV repair shops out there - I just seem to pick the wrong ones, and when it comes to having them repack bearings, how do you know what they actually did?

I have had a couple of bad experiences in this regard.

Many years ago with am SOB, I paid the dealer I bought it from a substantial amount for "pre-delivery work" I particularly asked if that included repacking the bearings and he assured me that it did. Had it not, I was prepared to pay extra to ensure the bearings were in good shape.

Well, one year later, I decided it weas time to check the bearings & when I did, I was horrified at what I found.

What grease was left was hard and caked and the rollers were all starting to break up and lose metal in all four assemblies. I was thankful I caught it before a major failure.

I'm no bearing expert, but I am a retired Mechanical Engineer as well as a long time restorer of old Brit sports cars (!), and I am certain those bearings were not looked at for many years - if ever!

Of course I had to change all the bearings.

You'd think I would have learned my lesson, but when I bought my Airstream from a dealer last year, I once more paid to have them repack the bearings. (I bought the trailer used, from an Airstream dealer.)

When I picked up the trailer, I was surprised that they had charged labour for the repack, but no charge for grease seals. When I queried this, I was told the seals were fine.

Personally, I don't think a reputable dealer would do a repack without putting in new seals, but I may be wrong on that point.

In any event, after one cross-country trip, (our first with this trailer) I just pulled the wheels recently to be certain as to their condition.

The front bearing was packed with that bright red grease, the back bearing had a different colour grease. So now I know what their repack involved, and I have decided firmly to always do my own repacks in future!

On another point, many people seem down on Chinese bearings but I'm not so sure they are that bad - in fact I think you will find that many bearings these days from companies such as Timken and SKF will be stamped "made in China."

I have a small trailer that I built to pull behind my motorcycle. I made it up from an inexpensive Harbor Freight Utility trailer that I cut down to size, with a Sears automotive luggage box mounted on it. The wheel bearings are Chinese and seem to be holding up just fine.

Cheers ......... Brian.

[safari62]

On another point, many people seem down on Chinese bearings but I'm not so sure they are that bad - in fact I think you will find that many bearings these days from companies such as Timken and SKF will be stamped "made in China."

I have a small trailer that I built to pull behind my motorcycle. I made it up from an inexpensive Harbor Freight Utility trailer that I cut down to size, with a Sears automotive luggage box mounted on it. The wheel bearings are Chinese and seem to be holding up just fine.

Cheers ......... Brian.[/quote]
Brian
My Timken replacement bearings were clearly marked USA. It is important to me for many reasons including quality of workmanship, materials used making those parts and the fact that because they are made here there are a few less people standing in the unemployment line.

I think you probably paid the same for the Chinese parts but the money by pasted the people that make the parts and went right to the top of the food chain.

We all have to make decisions about what we drive, eat and send overseas to be made by someone else. I feel better that my US made axle now has all us made parts. I am sure the executives at Henchen were able to add a few more golf vacations during the year by using Chinese labor. Good for them. Not for me.

Gary

[Gene]

Originally Posted by AirsDream

Most "experts" will tell you never to use a compressor to blow grease or solvent out of a bearing ... risk is that it will spin a race or roller (or ball) up to a very high speed (dry) and score / gall it.

If you blow the grease out from the side, they shouldn't spin, or if they do, they wouldn't go as fast as they do when rolling down the highway.

If you blow on the face of the rollers, that's a different story.

Gene

[Gene]

Originally Posted by Wingeezer

Gene,

Just curious as I have not done this yet on our trailer....... when you tap the seal out with a dowel or similar, are you not actually tapping on the inner bearing, which in turn hits the seal and knocks it out? End result of course the same.

I wish I could remember, but I can't. Ask me again next Spring. If I were tapping on the bearing, the bearing is pretty strong from that side and I could see no damage on any of them. About 6,500 miles later and they're still rolling.

As for Chinese vs. US bearings, I think Chinese made bearings can be as good as any others if the US company is carefully watching the process and making sure the bearings are made correctly. The latest story about Chinese made Goodyear Marathons was that the Chinese tires weren't up to Goodyear standards, so they cancelled the contract and are making them here again. Junk can be made anywhere including the US. Nonetheless, we avoid Chinese made stuff with strange brand names. In the 19th century, Europeans complained that US made things were poorly made just like we complain about Chinese made things. Good or bad stuff can be made anywhere; it depends on the manufacturer and their standards. Badly made Chinese products sold by US companies are just as much the responsibility of the US company as the Chinese.

Gene

[Kevin245]

Originally Posted by AirsDream

Most "experts" will tell you never to use a compressor to blow grease or solvent out of a bearing ... risk is that it will spin a race or roller (or ball) up to a very high speed (dry) and score / gall it. I'm not sure whether those experts are right, but it seems to be a bit of received wisdom. I personally have occasionally ignored those experts, but a) only using pretty low air pressure, while b) physically holding everything tight in an absorbent rag so that nothing can move. No bearing failures have resulted, but it's probably tempting the gods. As always, YMMV.

I use solvents routinely to clean bearings and bores. The primary issue with using compressed air is the concern of dry spinning the bearing, which could cause scoring and subsequent failure. Dry spinning, even at low speeds, is bad news for bearings.

I'm not aware of solvent causing problems and I've used it for years to remove old grease when servicing bearings. The key is to change dirty solvent and use clean solvent for the final cleanings to flush out residual crud and avoid re-introducing contaminants into the crooks and crannies. Cleanliness is the key. I always replace the seals, it's cheap insurance to me.

Regards,

Kevin

[Gene]

Originally Posted by Kevin245

The primary issue with using compressed air is the concern of dry spinning the bearing, which could cause scoring and subsequent failure. Dry spinning, even at low speeds, is bad news for bearings.

I don't believe all the grease is forced out of the bearing with compressed air unless solvents have been used before the air is applied. There's a thin film of grease left by the compressed air and thus the rollers are not dry. They are also under no stress. These bearings undergo a lot of stress rotating at high speed in normal use at temps a bit over 100˚ in summer. Compare that with a roller rotating a little under no stress with a greasy film on it at lower temps. I suppose when they are hand packed with grease, they roll dry until the grease is worked into the bearing.

I worry more about which solvent to use and what its effect is. Do small amounts of solvent remain in the bearing and compromise the grease? What is the effect of rolling the rollers when only solvent is in the bearing? Just how tough are the rollers?

This is an interesting discussion and will probably make all of us better at this.

Gene