Poll! What causes outer axle bearing failure?

[kgrant]

Just seeing what people beleive the main cause of outer axle bearing failure is on AATV's. Contamination (water, dirt, ect), or structural (bearing not sized for application).

[Rock Doctor]

I think there are many factors to consider (Contamination being high on the list), but the biggest, in my mind, is that the outer bearings see more stress/impact loads. As weight is added to the machine, load is transfered from the tires, through the axle to the outer bearing. As axle length increases, the load increases on the outer bearing, example: Axle extensions.
Front and rear bearings seeing the most of all, as they seem to see the most impact loads, dropping into holes, climbing out of holes, bumping off trees.

So, for me the fastest way to damage outer bearings is to haul heavy loads with Supertracks on.
Heavy weight in Argo = more load on outer bearings
Axle extensions = load increase on all outer bearings
Add Supertracks = added stress to front and rear outer axle bearings

This is part of the reason for bearing extensions on Argo front and rear axles. The closer you can get the bearing to the axle hub (load) the longer it will last.


RD

[6X6]

I think many factors contribute to the failure, but they simply were not designed for an anphibious environment, or for the stresses the AATVs put on them. I spoke with Whipper recently and he told me about a conversation he had with a bearing manufacturer. They are designed for agriculture, conveyers, and food processing machines (The triple sealed). I grease mine anytime I swim or go into deep mud, so they will hopefully last a while, but I don't think I can blame the ultimate failure on the contamination, but rather the fact they are not designed to deal with that contamination or the stress. I'd love to see a setup like on my trailer (Boat) with not just heavy bearings but spring loaded grease fittings that prevent ANY water/muck from entering unless you let-em run out of grease.

[Bw6]

Ball Bearing Life

Ball bearing life depends on many factors as we all know. But the biggest cause of bearing failure is water contamination. As little as .002% water mixed in with the grease reduces your bearing life by 48%. I have calculated that those triple seal bearings should yield about 2500 hours at an average speed of 10 mph. Most get about 250 hours.

The main problem is water contamination. So how can we get longer life? By improving the water seals, which is easier said than done. I have tried changing the Argo seals with double lip/garter spring seals, which is about the best I can do with the current Argo bearing housing.

A roller bearing design would handle the track induced maintenance problems, but it would need a whole new bearing housing to accommodate it.

[lewis]

Chain tension

All posts were right on the nose about the contamination external loading, tracks and track extensions. All good points. I would like to add to these points.

Chain tension is another item that will damage the bearings in these machines. I have a limited amount of experience with these machines as a reference but have done mechanical work all my life. Worked on electric motors, high speed winding machinery, oil mist bearing systems and ceramic bearing motors. One item that a lot of people overlook is.

How we handle and install them will have a direct reflection on how long they will last. Just for grins and giggles cheap bearings will not last long by design.

My Avenger and maybe some other models as the frames flex the chain tension devices will ratchet up a notch as the frame goes through some heavy flexing. Noticed mine doing this. Released the tension and all is fine. Last ride did a lot of heavy flexing and the same reaction occurred. These chains were as tight as Dick's Hatband. I plan on changing these tension devices to the courser tooth tension device that Argo produces. Chain tension increases the load on bearings and housings causing premature wear and failure.

The Argo Centaur: Runs a oil bath for the bearings and has no problems with contamination, but we are talking about a very high end machine also. $40-60 thousand dollars. Not for recreation use.

Didn't see anyone mention this as a factor.
Lewis

[kgrant]

I guess you could go and replace all the outers with something like this, but then you still have the sealing problem.

1-1/4" Type-E Four Bolt Flange Bearing

[philipatmaxfour]

Too much chain tension damages bearings

All posts were right on the nose about the contamination external loading, tracks and track extensions. All good points. I would like to add to these points.

Chain tension is another item that will damage the bearings in these machines. .........

My Avenger and maybe some other models as the frames flex the chain tension devices will ratchet up a notch as the frame goes through some heavy flexing. Noticed mine doing this. Released the tension and all is fine. Last ride did a lot of heavy flexing and the same reaction occurred. These chains were as tight as Dick's Hatband. I plan on changing these tension devices to the courser tooth tension device that Argo produces. Chain tension increases the load on bearings and housings causing premature wear and failure

Didn't see anyone mention this as a factor.
Lewis

Hi Lewis I am sure that excessive chain tension is a problem, I just added tracks and believe that chain windup with tracks exagerates the problem. I am a bit confused about your comment on courser tooth Argo tensioners, My Avenger is an 06,a year older than yours?, and it has courser (less teeth but bigger) on the tensioners than previous Avengers. Apparently to stop the teeth from jumping back? Which do you think cause less over tensioning?
Nice to see you enjoying your machine so much.

[lewis]

Hi Lewis I am sure that excessive chain tension is a problem, I just added tracks and believe that chain windup with tracks exagerates the problem. I am a bit confused about your comment on courser tooth Argo tensioners, My Avenger is an 06,a year older than yours?, and it has courser (less teeth but bigger) on the tensioners than previous Avengers. Apparently to stop the teeth from jumping back? Which do you think cause less over tensioning?
Nice to see you enjoying your machine so much.

Hi philipatmaxfour
My machine for some reason has the finer toothed chain tensors. When you place it beside the course type you can really see a difference. The larger more spaced tensors were a upgrade. It requires the machine to flex more before it will ratchet up. With the smaller teeth it is easier to move up a little at a time. The last ride was pretty rough and the machine was flexing a lot!!. When i returned home i rechecked it and it had tightened up again. This seems to occur mostly with the front chain tensors. The big tooth tensors is the better type to have. I will have mine changed before the Busco ride. Evidently you have not had this happen and that is a good sign.

Chain windup seems to be more of a problem with the rubber tracks than with the plastic ones. The rubber ones will not allow much or any slippage between the tire and the track. I don't run track so this is not a problem for me but i do know it exists . This will really put some bearings in a bind and other parts also.

I really enjoy the Avenger and now it has 97 hours on the clock. I keep a really close watch on chains, tensors and bearings. It has been a excellent machine. and a blast to ride.

Nice talking with you Philip

[Amphiman1]

bearings

Also, beware of cheap foreign bearings.. lets say a bearing is 14.00 but a "cheap" bearing is 6.00 You get what you pay for too... The same with "made in china " chains too....

[lewis]

Finally someone said it.

Steve, Thank you! That's all i need to say.

[kgrant]

What would you guys consider an acceptable number of hours for an outer axle bearing to last under normal AATV use. How about one with tracks and extended bearings?

[6X6]

Also, beware of cheap foreign bearings.. lets say a bearing is 14.00 but a "cheap" bearing is 6.00 You get what you pay for too... The same with "made in china " chains too....

And tools, as per my "Taiwan Teddy" Ratchet photo post, sometimes, what you pay for is a busted knuckle(didn't break this time, I did once, though). As per Whipper I will be using Diamond Chain and Timken/Fasner bearings, all made in the USA!

OH, normal lifespan? IMHO there isn't one. How you ride, what conditions, do you swim and how much, how often you grease, how much load, do you tow, how much with and without tracks?..... Way too many variables in my opinion, just check for slop or notchiness periodically.

[kgrant]

I don't know how other AATV's are setup, but on my Hustler the bearing is what locates the axle in the vehicle. So, at times there will be a very high thrust load on the bearing, which from what I can find, is something that this type of bearing isn't designed to handle.

I know there are better bearing setups for this application. Why are they using the same type of bearings that were used in the 70's? Maybe it isn't cost effective to redesign them? Maybe there isn't a need to and I'm just trying to reinvent the wheel?

I would say that Argo has the best sealing setup. What does argo use for a bearing? I know that Max uses the same type that my Hustler is using.

What is the Muddox using for a seal/bearing?

Do they all use the bearing to locate the axle?

Here is a link to some information I found on bearing load vs life calculations. They talk about thrust near the bottom.

http://www.iptci.com/pdf/Bearing%20Selection.pdf

[wfo]

Ive already tried those type e bearings from the company dodge..i tried them about 16 years ago.. And they are ok for a few years but the housings are brittle..and then they fall apart...of course they have to be milled flat before you can install them....good try though