Crankshaft bearings (again)

[Guydreads]

So I went to a local chainsaw dealer, and he picked up some bearings for me. Very high quality evidently by the feel... but, there's this:

 

Do I need to return these to get open bearings? I was reading something about popping seals out and what not. Is that possible with this? I'm a newbie when it comes to bottom ends, this is my first one and I'd rather not blow it up. Evidently this isn't going to work as is, since no oil will get to it.

[Guydreads]

Also I did find a video of how to remove it (the shield)... I just want to make sure that it's safe

[Real1shepherd]

You need to return it to the original configuration, yes. Usually, that's both dust shields off and a seal in the hollow of the crank case. Make sure the bearing thickness is the same as OE so your crankshaft seal will fit in the hollow as OE.

Kevin

[Guydreads]

Yes, it is the same as the original in every way, I'll send a pic with the shields removed once I get to it later

[Real1shepherd]

Almost all bearings and seals in this kinda application are now coming from China. I hate that in almost every way possible.....but what are you gonna do...... :

I've got CV boots on the front axles of my car. I get three-four yrs on them before they crack and start leaking/slinging grease. And yet the half axles boots in the rear are original.....30yrs. Obviously, it's a material/manufacture issue. Replacing half axle boots every three-four yrs is not routine maintenance.

Kevin

[Guydreads]

At least on the packaging it says made in Portugal, I don't know if that's really true though

[Al_Smith]

The subject of sealed bearings can become very controversial .Conventional thinking suggests that without additional  methods of lubrication might  cause a premature failure. Not really  the entire truth .
For example the highly precise spindle  bearings on high speed CNC machinery  that can cut parts to micrometer tolerances  use sealed bearing .Those bearings operate at speeds far exceeding what a two cycle engines operate at .You can Google it if you want or argue about it  ,makes me no difference .   

[Real1shepherd]

At least on the packaging it says made in Portugal, I don’t know if that’s really true though

That would be another manufacturer of origin. I found bearings in my car made in Slovakia, now replaced by China. Distributor cap made for Bosch in Spain etc. Bosch has gotta be the worst though with their hidden tiers of quality.

Kevin

[DHansen]

Moog is another  company that has lost quality and customer support.

Bosch has levels in there product line that reflect quality.  Low end blue box vs high end yellow and black.

[Real1shepherd]

I didn't know that about the color schemes!

Kevin

[DHansen]

One of our suppliers, Brake and Equipment, will say "Well we have blue box".  When the Quiet Cast and Premium line stuff is sold out.  It is the companies attempt to compete with the low priced Asian imported items.  It's difficult today to bank on a brand name.

[Guydreads]

One more question. Is it crucial to remove every last spot of grease? How will that affect the running of the saw? 

[sablatnic]

One more question. Is it crucial to remove every last spot of grease? How will that affect the running of the saw?

I don't, I just clean in a cup of petrol or flush it with brake cleaner. I get most of the grease off, but not all, and haven't had problems. 

[Real1shepherd]

One more question. Is it crucial to remove every last spot of grease? How will that affect the running of the saw?

Grease from where....after you remove the shields? If so, not that critical, as the saw gas mix will eventually replace the grease inside the bearing.

Kevin

[joe_indi]

When I was a novice on these engines around 27 years ago, one of the first saws and brushcutter that I had before me had 6202 and 6201 crank bearings. I thought the repair of that saw would be like a dream since 6202 bearings are what that are on ceiling fans and small motors and less than a dollar each. Zipped of to the nearest SKF bearing outlet where I got my first lesson. All bearings are not made the same they have many variables and using one type for the other is the start of the road to disaster ( for the engine).
These too were made in Portugal FAG.
The dealer referred to a reference book and told me the specs for the original bearings 
Speed rated for maximum 16000 ( maybe 18000) rpm. 
Lubrication by 'Petroil' ( petrol & oil mixture)
Application rotating shafts with constant impact ( of combustion?)
C3 which means the surfaces have thrice the clearance compared to normal bearings.
Price put it about 20 times more expensive than a ceiling fan bearing!
And, not available off the shelf here only by special order.
The only C3 bearings available, were of a different size, lubrication by gear oil, at much lower rpm, for gear boxes.
Lesson that i took back with me was Don't try substitutes when it comes to crankshaft bearings.
Clone saw bearings, if i understood right are made into C3 by pre running them with some kind of grit to wear out the racer and balls to give an extra clearance. Got them with the grit still in them.
Lasted for less than a week.
A Chinese company Zomax sent us some 361 clones with the covered bearings. Failed faithfully like fireworks going off.

[Guydreads]

I had my dealer order it for me, and he got the correct tolerance bearings. 15 bucks a pop