Sears "pre" block grinder. HELP!

[garymtx]

This was thrown in with some other stuff at auction awhile back. It's a Sears pre block grinder, model 115.7566 TYPE CR16E. There's a reason it was free. The whole left side bearing housing had been broken off and welded back on by someone that didn't know how. Looks like bubblegum stuck on there, hahaha. I AM in the process of refurbishing....Anyone know what bearings this thing takes? I have them out and the numbers are Z97502 and ND3202...BOTH of these numbers are on the same bearing. One more thing, it needs a new capacitor and the old one has NO markings......Hmmmm..

 

[Rileysan]

This was thrown in with some other stuff at auction awhile back. It's a Sears pre block grinder, model 115.7566 TYPE CR16E. There's a reason it was free. The whole left side bearing housing had been broken off and welded back on by someone that didn't know how. Looks like bubblegum stuck on there, hahaha. I AM in the process of refurbishing....Anyone know what bearings this thing takes? I have them out and the numbers are Z97502 and ND3202...BOTH of these numbers are on the same bearing. Here's the rub, the existing bearings are sealed, everything I'm finding with those numbers are NOT sealed...………..????? One more thing, it needs a new capacitor and the old one has NO markings......Hmmmm..

Ball bearings have been internationally standardized since at least WWII. Bearing numbers reflect a size (in metric) and grade (kind of a duty rating) and I think seals are optional.

If the replacement bearings you are looking at do not have seals, find another manufacturer. You want sealed bearings in your grinder.

I have a bearing book at work that will tell me how to decipher those numbers. My 65 yo Romanian boss could tell me without a second thought as he had to learn how to decipher sizes based on numbers, and numbers based on sizes during his millwright training in the "old country". If I remember tomorrow, I'll take a look. That, or someone here has them memorized already!

Brian

 

[Provincial]

ND3202 sounds like a New Departure number. A 3202 is a specific bearing size. That number would have suffix letters to indicate the type and location of the seals. There are even bearings with shields (not seals) that allow excess grease to escape when installed where there are grease fittings. If you call a bearing house and ask for a 3202 bearing that is sealed both sides, they can fix you up easily. They would be angular contact ball bearings and would have a 35mm outside diameter, 15mm bore, and be 15.9mm wide. Often, the bearing supply stocks only sealed both sides bearings, and if you don't want the seals, you have to pry them out yourself.

 

[930dreamer]

I think ZZ are sealed?

 

[FrankLee]

This was thrown in with some other stuff at auction awhile back. It's a Sears pre block grinder, model 115.7566 TYPE CR16E. There's a reason it was free. The whole left side bearing housing had been broken off and welded back on by someone that didn't know how. Looks like bubblegum stuck on there, hahaha. I AM in the process of refurbishing....Anyone know what bearings this thing takes? I have them out and the numbers are Z97502 and ND3202...BOTH of these numbers are on the same bearing. Here's the rub, the existing bearings are sealed, everything I'm finding with those numbers are NOT sealed...………..????? One more thing, it needs a new capacitor and the old one has NO markings......Hmmmm..

I saw this same post on another website and one of the replies seem a little off to me:

you do NOT want sealed bearings on a grinder, you want shielded, e.g. ZZ , sealed will just heat up more

So, I ran a very unscientific test on my own 115.7566 WITH sealed bearings.
https://www.garagejournal.com/forum/showthread.php?p=5938522&post5938522

Before starting, the housing around the right bearing was 66.4 degrees.
After 10 minutes running with no load, the housing around the right bearing was 78.6 degrees.

I realize that the bearing would have to be warmer than 78.6 to heat the housing, but on my machine, I don't think that 12 degree difference is a big deal. I would not hesitate to use sealed bearings again.

​

 

[garymtx]

Thanks Gents!! All great information....I believe I'll go with the sealed bearings and not shielded. There are no grease fitting present even though shielded is what came out of it. I believe the zz designation does indicate a shielded bearing, even though there is no zz on these. I will keep ya'll updated as I continue the refurb......Any thoughts on the capacitor sizing???? I'll get some pictures of it uploaded asap, it's an old paper wound one. Best regards!!! Gary

 

[garymtx]

Quick update...Bearings ordered. Torn down, cleaned and primed. Here's the side that had the "bubble gum weld" after grinding, filling and primer.

 

[exmaxima1]

If it doesn't work out, I have a spare left side housing and guard. PM me.

 

[garymtx]

If it doesn't work out, I have a spare left side housing and guard. PM me.

Thanks exmaxima1! I think I'll be leaving it as is for now. Just waiting for the bearings to get here for reassembly. I'm going to put polishing wheels on it. It will be a nice addition. I have a vintage Baldor on a stand for serious grinding and a variable speed Delta with knife sharpening "strops", so the buffing wheels will save me switching out wheels. I have a knife collection to maintain....I'll keep you in mind if plans change..

 

[garymtx]

If it doesn't work out, I have a spare left side housing and guard. PM me.

Does your capacitor have any markings? Mine has none, and I'm having a hellava time finding the correct one. I know the 1/3 hp "block grinder" pulls 3.8 amps, this one pulls 5.5..... Thanks in advance

 

[torqueman2002]

Does your capacitor have any markings? Mine has none, and I'm having a hellava time finding the correct one. I know the 1/3 hp "block grinder" pulls 3.8 amps, this one pulls 5.5..... Thanks in advance

See my reply, with pictures.
https://www.garagejournal.com/forum/showpost.php?p=7669704&postcount=3

 

[garymtx]

See my reply, with pictures.
https://www.garagejournal.com/forum/showpost.php?p=7669704&postcount=3

Thanks! got it!

 

[Farmall450]

See my reply, with pictures.
https://www.garagejournal.com/forum/showpost.php?p=7669704&postcount=3

A-ha, here's the expert

 

[garymtx]

See my reply, with pictures.
https://www.garagejournal.com/forum/showpost.php?p=7669704&postcount=3

One other thing. I will be reassembling in the next day or two. There is a single spring washer that goes on the armature assembly but I can't remember WHERE it goes (should have taken more pictures haha). Can you advise me where it goes? Cant find any diagrams for this old gent. Thanks in advance,
Gary