Bearing issue for a pulley

[malk315]

Hey guys -- apologies this isn't saw related, but one way it is connected is the bearing pocket on this pulley is just like a chainsaw bearing pocket on a husky case half (the pulley is even orange

I spun a bearing on my kioti ck-20 mower deck -- it's one of the greaseless idler pulleys.
I took the number off of it and it is 6303Z. The original bearing is GMB part # 6303Z and I found an SKF part #6303Z with the same specs (bore and outer diameter are identical so it will work) so I just ordered one.

Well -- the new bearing is missing a cover on one side -- any ideas why? I'm assuming if I run the new bearing w/o something covering the exposed side crap will get in there and ruin it?

Here's some pictures to make it completely clear -- first picture bearing on the left is new one, bearing on the right is old one, pulley you can see the pocket and snap ring to hold bearing in there (will need to heat pulley and cool bearing to get it in the pocket similar to a saw it is tight):


In this second picture below all I've done is flip over both bearings -- the old bearing is covered on both sides, the new one has this side exposed. I'm bummed -- I couldn't find the original bearing GMB brand anywhere and this mower deck hasn't been made for several years now -- it's the DMM-60 model from Kioti and is Italian made -- possibly by Del Marino. Any ideas on how I could get a GMB original bearing or any other ideas would be appreciated.



Sorry to booger the saw forum with this, but perhaps it could be moved to off topic area after a few of you guys have seen it.

Thanks guys -- I'm learning, remember I'm a desk jockey by trade but not afraid to wrench on saws and other mechanical things and I enjoy it and want to continue to learn!

 

[jacob j.]

Yeah when you order bearings, it's the trailing numbers and letters that indicate how the bearing is set-up. A bearing that has RS somewhere in the string means that the bearing is rubber shielded. A bearing that has ZZEDS means that it's a ZZ rated (top speed and load) "E" electric motor bearing that is DS double-shielded.

That's definitely an application where you want a double-shielded bearing. The good news is though you can save that one-side shielded bearing for a chainsaw, like the flywheel side on an MS-660, and install it with the single shield facing outward to the case seal.

 

[malk315]

Yeah when you order bearings, it's the trailing numbers and letters that indicate how the bearing is set-up. A bearing that has RS somewhere in the string means that the bearing is rubber shielded. A bearing that has ZZEDS means that it's a ZZ rated (top speed and load) "E" electric motor bearing that is DS double-shielded.

That's definitely an application where you want a double-shielded bearing. The good news is though you can save that one-side shielded bearing for a chainsaw, like the flywheel side on an MS-660, and install it with the single shield facing outward to the case seal.

Thanks for the response. So if I found a 6303ZDS it would be shielded on both sides like my original?

 

[malk315]

I figured it out w/ a little google! I need a 6303ZZ bearing... dang it the GMB one isn't really marked per standard.
Hopefully I can get one locally so I don't have to wait as long -- lawn needs some serious help!

Thanks

 

[67L36Driver]

Back in the olden days, Marlin Rockwell Corp. (MRC) had the most user friendly and logical bearing numbering system.
100=extra light
200= light
300 = medium
400 = heavy
Bore was number 01, 02, 03 etc.
So, your 6202 of today was just a 202.
Suffix Z is seal one side. S is shield.

So simple it was how we inventoried all our ball bearings despite the SKF or slacker number.

 

[drf256]

Can't you reuse one of the caps off the old bearing Eric?

You may ruin one side trying to get the other off, but you only need one

 

[Mattyo]

just some comments

Doc, I like that idea... tear one of the old shields out, then tap the other side out gentle...

I know 6202zz is double shielded... 6202-2rs is double sealed.

the flywheel side on a 660 is 6203 bearings... so I don't know what the difference is between a 6303 and a 6203.

 

[Mattyo]

ah 6203 - 17mm x 40mm x 12mm
6303 - 17mm x 47mm x 14mm

the 6303 will not fit on a 660

 

[Mattyo]

eric here is a 6303 double sealed...

http://www.ebay.com/itm/6303-2NSE9-...932770&hash=item1ecc6081b3:g:JekAAOSw7FRWUG0s

I dunno why you wouldn't want sealed vs shielded here... sealed would prevent crud from getting in there i would think. shielded just keeps out the big pieces / damage .... i would think

 

[Al Smith]

If that idler calls for two bearings stacked on top of each other what would happen if you installed them shields out,open races in? If it would jam up I'd bet it would take a long while before it did .You already have the bearings .

 

[67L36Driver]

Shield clearance with the inner race is a lot closer than you give it credit for.

As above, stack them shields out and move on.

 

[Mattyo]

Shield clearance with the inner race is a lot closer than you give it credit for.

As above, stack them shields out and move on.

Ie....the shields provide pretty good protection against dirt and debris? Fair enough

 

[malk315]

Hey guys. Thanks for the responses. It's only one bearing so I can't stack em. I found an SKF 6303ZZ that I ordered last night. It was like $6 I think and they will priority mail it so I'll have it in a couple days. The original just has the metal covers and no special seals and it lasted for 12 mowing seasons. So it does seem the metal covers keep the crap out pretty well. Glad i learned some new info and thanks for the help guys. Love it that this bearing is like a 660 crank bearing. The pocket in the pulley might as well be a saw case half

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[jacob j.]

Hey guys. Thanks for the responses. It's only one bearing so I can't stack em. I found an SKF 6303ZZ that I ordered last night. It was like $6 I think and they will priority mail it so I'll have it in a couple days. The original just has the metal covers and no special seals and it lasted for 12 mowing seasons. So it does seem the metal covers keep the crap out pretty well. Glad i learned some new info and thanks for the help guys. Love it that this bearing is like a 660 crank bearing. The pocket in the pulley might as well be a saw case half

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My bad- I thought your post said 6203, not 6303. A 6303 is too big for most saws, except for the larger, older Solo saws and some other Euro saws. A 6203 is what fits the flywheel side on the 064, 066, MS-650, and MS-660 saws.

 

[malk315]

Finally got the right bearing. Heated to 400 and bearing in freezer but still needed coaxing. Used old bearing as I don't have a socket big enough. Then tapped the old one back out after new one seated home. Installed snap ring keeper and it's spinning nice. Once it cools I'll put her on the mower deck. Be mowing that hay field... Err... Lawn finally!

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[malk315]

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