Are these bearing already greased?

[blinky]

Ordered bearing for my eq6 stripdown and regrease. I'm wondering if they are already greased or if I need to remove the dust cover and grease? Looks like there are traces of oil on the packet which would leave me thinking they are oiled- which then leaves me wondering have I to remove the oil and add grease, add grease without removing the oil, or just leave as is....

[teoria_del_big_bang]

If it is a genuine SKF then it will be pre-lubricated and should not need the dust seal removing.

 

Steve

[Physopto]

This type of bearing is sealed for life. Removing the dust covers will damage the integrity of the bearing. The bearing leaves the factory with the exact amount of the correct grease in it. (or should do unless a cheap knock off). SKF are generally of good quality.

Derek

[blinky]

Cheers guys, leave as then - no reason to suspect its a knockoff or anything, bought from a bearing company in England

[Physopto]

Probably made in China Then .... 😂

 

[blinky]

Says made in Italy on the pack...

[Tomatobro]

SKF have a table which specifies the percentage grease volume vs load and RPM factors.

[wxsatuser]

The dust seals on SKF are the hardest to remove.

We do remove seals on all makes at work as the amount of grease is pitiful and we get early failures.

For your application it's a reasonable amount of grease in there so ok.

[Rocket Stars]

SKF (Swedish Ballbearing Factory, translated) Has manufacturing plants where the customers/industries are. Italian cars needs ballbearings.  

2008 is a standard ballbearing size. 2rs stands for dubbelsided rubber seal. Those are lubricated for life. 

Still are amazed over mount threads. Where ppl are "reinventing" lubetechnology. 

[blinky]

Just looking at this again - according to the very well respected Astrobaby site, the bearings are supplied ungreased and the seal should be removed and the bearings greased, im confused again!

http://www.astro-baby.com/EQ6-Supertune/EQ6 Super Tune Guide.php

[MarkAR]

Put finger in hole of bearing, use finger of other hand to spin outer case as hard as you can. If it spins freely for a long time and you can hear it rattling then grease them.

If it slows fairly quickly and is pretty quiet the it is already greased.

You have the 2RS1 bearings, he shows the 2RSH. Different specifications.

Edited April 6, 2020 by MarkAR

[Rocket Stars]

All sealed bearings from reputable manufactures, are greased to the right specs they are designed for. The seal increases friction little. But keeps dust ect away. 

If you remove the seal. The grease will collect all dust and debris ect. Trust me. I once was in the aviation industry. We never, ever practice that. What ever ppl says. This is "home made ideas" 

If you want non sealed bearings. Its ok to remove the seals. But in that case. One should buy non sealed bearings. That also are cheaper.

Just use them. 

 

Edit. Just red the yellow marked text. "lubricate with lithium grease" That is completely wrong lubricant for bearings! 

Edited April 6, 2020 by Rocket Stars

[omo]

The bearings will be greased at manufacture but providing you dont overpack them flipping out one seal and adding grease does increase the bearing lifetime, regularly do this with motorcycles after noticing that 3 new hondas i owned ran out the first bearing at 10k miles, i doubled this by adding extra grease.

I can see why its not acceptable for something like aviation though with high rotational speeds possible. It was explained to me by someone that grease will expand due to heat and can pop a seal if there is too much in there.

Should not be a problem with  a mounts bearings.

[blinky]

Take I need to grease these ones then?

[Starflyer]

Yup, grease the two thrust bearings, but not too much, they're a big cause of friction and overgreasing them will make the mount hard to balance.

[blinky]

Cheers, will give them a wee smearing of grease then, think they have some oil on them already

[Rocket Stars]

1 hour ago, omo said:

The bearings will be greased at manufacture but providing you dont overpack them flipping out one seal and adding grease does increase the bearing lifetime, regularly do this with motorcycles after noticing that 3 new hondas i owned ran out the first bearing at 10k miles, i doubled this by adding extra grease.

I can see why its not acceptable for something like aviation though with high rotational speeds possible. It was explained to me by someone that grease will expand due to heat and can pop a seal if there is too much in there.

Should not be a problem with  a mounts bearings.

Also did that on dirtbikes. But its more about protecting from the wet grimy stuff. 

On my RD 500 and RGV 500 I used to have. I also had to change berings quiet often. But I think its more due to engineering problems. Hard to find bearings that holds up to the loads in those sizes. Atleast to a production prize point. 

My buddy who raced TZ250. We changed to cheramic

main bearings. But in the end. It just did cost  more when the rest of the engine sized up. Good times! 😊