chipper bearing failure

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Big Jim

ArboristSite Lurker
Joined
May 19, 2006
Messages
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Location
new haven CT
I have a Morbark model 13 I bought brand new in 1998 . I can only get 750 to 800 hours out of a set of drum bearings . In 2002 the first failure I was told I was over greasing the bearing (I doubt it).I cut back the grease on the next set and here it is 2006 and they failed again (50 hrs. less than the original set).
This machine is primarily used for residential work as we have a Model 16 Morbark for land clearing so i dont think it is being overworked .We are REAL good about sharp knifes and all adjustments(anal the kid says).We use it but dont abuse it .
Anybody else got any info or having the same problem?(Only problem I ever had with this machine)

If it was easy women and children would be doing it.
 
I dare say chipper bearings would be the purge grease type. You know, a daily pump of grease will enter the bearing whilst the old grease is pushed out and flicked off somewhere.

I couldn't see them as a sealed bearing, just too much dust and vibration ... they'd need to be purged.

Try to get low down on the type of bearings. If you infact have sealed units and you are pumping them often and trying to purge you would have broken the seals and possible built up too much grease/pressure inside the rollers resulting in premature failure.

There are many different bearing manufacturers making varying quality stuff. I go down the bearing shop and buy the best precsion jap bearings I can. Maybe they're fitting cheap ones or wrong style.

Hey, I just had to strip my stump grinder and replace 2 bearings. I was a very lucky man and actually had the bearings tap off! That's a big deal, usually got to cut them off or ditch the shaft. I got 110 hours out of this set and 20 hours out of the originals. The genius manufacturer has bearings you cannot grease at all ... no grease nipples and if there were grease nipples they dont line up with the groove in the bearing.

So you pack them well, whack them in, and cross your fingers for a while. when you here the metal on metal grating sound it's time again, and the exercise costs around $550 in parts alone. And you cannot get to the bearings for a grease job without stripping the machine.:dizzy:
 
Just an odd thought here...

Bearings, and not only on chippers....

I read somewhere that bearings can live longer if the lubrication is the correct "weight". Does that make sense?

Okay, grease can be had in numerous weights, and with various additives. Some are thicker, some are thinner. Some have moly, some don't. Some are long fiber, you get the idea.

Anyway, I read somewhere that matching the lubrication to the bearing can probably double it's life. Now, I am going to go WAY out on a limb here and say that a chipper being a high speed machine would need a thinner grease that would "flow" better. But, not too thin. Maybe a synthetic?? for the high temperatures? On the other hand, a slower bearing under a heavy side load would need a thicker grease to carry the load better.

-Pat :jawdrop:
 
I know what a purge bearing is . This is a Timken purge type bearing manufactured for dodge manufacturing. It has a split cap that has been redesigned from the original set of bearings.The spec on the grease is NGL 2 lithium grease which is pretty much all I use on all my machines.
If I got 25 hours out of a set of bearings on my stump grinder I would think about finding a different bearing manufacturer or getting rid of that machine.I just recently replaced one of my stump grinder bearings and it had 1200 hrs on it.it is also a purge type timken bearing .Screw those Jap bearingings. I cant imagine a stump grinder manufacturer putting a sealed bearing on a cutter wheel shaft.Even my little Dosko walk behind which I bought in 1994 has only had the bearings replaced 1 time.Grease is cheap when given the alternative.

This is why we drink beer.
 
Get your berarings straight

There is no way, and I mean NO WAY, that you should have only gotten twenty hours on a set of grinder bearings unless you were actually using sand instead of grease. Even here in FL where the ground is about 50/50 sand and dirt we are getting much more time out of a set of bearings. As for the Morbark bearings....we used to be a Morbark dealer and still service as well as sell Morbark chippers from time to time. Down here, 750-1000 hours is fairly average on a set of bearings. The grease type is an issue, but not a huge one if you are using the machine on a regular basis..i.e if the machine is getting used daily, it is getting greased daily (or is supposed to), right? However, I am not all-knowing when it comes to bearings, and the causes of their failures. I am, however, always willing to learn more. Throw some knowledge in my direction if you can!

joey c.
 
Grease !!

Hi Folks,
Just a short post,read the specs on your container, This is where you will find what grease for the wright application,don't mix your soaps or it goes to nothing,use quality bearings..this help for long liverty of your bearings..try to find a grease that will cover a broad range of apps so there's less likely hood a cross contamination,..lastly use it regularly.
Hope This Helps
 
Big Jim I know how frustrating it can be to ask advise here sometimes. You get treated like a moron sometimes because sometimes people ask some (it seems like stupid questions) . I have been on both sides. Ekka is a helpful (Bloke) whatever a bloke is. He didnt mean to insult you.
 
It takes time to type everything that you guys need to understand about lubricants, maybe you can learn then you can share with everyone::cheers: :
If you know something useful give us the benefit of the doubt (for being duhs) and post something of what you know so that we may live vicariously through your implied knowlege. Just posting 'I can help.' smacks of some sort of hidden sales pitch imho; my local mechanic can help and take a minute or two to explain why something will or will not work. Most everyone here knows a thing or two about lubrication and those that don't and ask are more than willing to learn a thing or two. If you are truly willing to answer e-mails with concise, usable, information then for dogs sake just post it here instead of keeping mysterious secrets, its kind of irritating ta me! My honest opinion :p

Sheesh! :monkey:

:cheers:
 
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Lubricants are very complicated most are on the right track but fall short because of the complex subject do as I ask and you will see.
Oooooooooooo, complex answers *Homer S. sr,* :monkey: :dizzy: :monkey:

No. :p

Wrong answer. Due to the complex nature of my mind I will endeavor not to ask you any questions or pay any further attention to your lame posts, sorry 'bout the feelings but you have about as much credibility as a (fill in blank here).... :notrolls2:
 
TreeCo you may be wrong----He is selling AmWay!!!!!

Amway is now Quixstar. I found this out when an old high school buddy tried the line, you know how it goes, a little digging and I found out. Lubeguy, you remind me of cops when they pull me over-"do you know why I stopped you sir?" I say-"why not tell me then we'll both know"
 
I don't think that it is a matter of learning. How can one learn if the "teacher"
won't teach? I guess we are so dumb that we cannot figure out how to use proper lubricants but we are able to run a business successfully. SHARING information is what this site is all about.
 
lubeguy, welcome to AS... don't mind the smartass's. that's standard fare around here :D

we really don't mean any harm... now anyone that choses the name lubeguy probably has a background in lubrication. you got me curious now....

now please tell us how to prevent high stress bearing failures!

Thousands of people run companies that's what they do but they still send their cars to mechanics,auto manufactures manufacture thousands of cars
and they still make mistakes that have tobe recalled.I don't mind sharing information I read you post we manufacture greases,I'm not going to get rich
selling you 1Tube of grease or 10 cases I don't ask that any of you buy anything i just tried to help and the smart ass got the other smart asses rolling do as I ask or you can do what you've been doing free country.:camera: get the picture.
 
high content moly grease gives highest protection factor I'm aware of.

CV joints specify moly grease. most common moly grease contain less than 5% moly.

lately I've had to order moly paste for air rifles. this paste is 90%+ pure moly and very expensive!
 
I would spend every day typing all the answers to the questions you're going to ask. I don't type fast as a matter of fact I'm slow as hell. Lubricants are trickie they give you what you think is the answer marketing not lubrication.

Look here, you asked Big Jim for his e-mail address, saying you would help him, now you say you would have to type all day. So, why not say it once, to all of us, and help out the people here with chippers? I figure it is mostly marketing with you, selling product, next come the claims. Well known brand name h.d. greases are as good as it gets. Same with engine oil, very exhaustive tests have been done with engine oil additives, they were all found to be bunk, use good oil and change it often. What is the product you are peddling?, be upfront and honest, this cryptic sh&t is lame.
 
I hope you don't believe in trolls.I bet you own a pet rock.:bowdown:
And I bet you have a pet troll! :p
Your evasive and flippant replies, lack of faith in our ability to understand things, and inability to type one useful or helpful phrase says it all.........................let there be luby twins! Treat people as you wish to be treat lube-dude, you sound like you just got outta high school and got a marketing job with dura-lube lol, sheesh, get a grip buddy! :dizzy: :dizzy:
I still have yet to see you post 1 useful piece of info amongst your drivel, stating the obvious doesn't count and most anyone who ever had a bicycle as a kid and a good dad knows what and how basic lubrication works fyi, most have gone far beyond too believe it or not, sheesh! I run some of my bearing raced machines at over 25k, no failures for years, litium/moly/teflon lubed...........gee what could that be?

Thphphphhppht! :monkey:




oi. :notrolls2:
 
There is no magic answer all I'm saying is you must understand the components of the lube you are using to understand it's capabilities and most fix it people have mostly bad information in their heads.
A lot of typing that's why I would rather talk.What is everyone so affraid of.
Good Night
Hm, I think this is why we read, most reputable producers of lubricants write the info needed on the packaging!

Right now, we're afraid of wolves in villager's clothing....

AAAAWWWOOOOOOOOOOO!

:p
 
bearings

If the bearings do not preform well take one and send it to a bearing company, doesn't have to be the one that makes that bearing, and ask if they make a better one, expect to pay 2-5 times as much for the new/better bearing but expect to get 4-5 times the life out of the bearings. By all means tell them what the bearings are for and ask how and what should be used for lube. Avoid the useless stuff lubman has said so far. Quality costs money and different grades of bearings have different costs. Figure you can spend as much on new bearings that can do the job as it costs you in down time, repair and rental of a replacement machine while you wait for repairs because of the bearings that fail early.
 
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