If you are rebuilding your snow thrower, many models from the 60's, 70's and 80's, use the same bearings for the chain drive shaft.
ST-323, 6-0200, 6-0201, 6-0202, 6-6212, 6-6213, 6-6214, 6-6215, 6-42ST01, 66-42ST01, 76-42ST01, 86-42ST01, 86-48ST01,
98-42ST01, 06-37SB01, 06-37SX01, 06-42ST01, 06-42ST02, 06-42ST03, 06-42ST04, 06-42SY01, 06-42SY02 and others.
The bearing part numbers are 107743, 100908, 101702, 101781, or 1968. If you have checked, you probably found that replacement bearings from Toro cost you around $60.00 each.
These are the bearings that are inserted into the 3-bolt flanges that hold the shaft on either end. They look like this:
The inside diameter is 3/4", and the outside diameter of the widest part of the outside is 52mm or 2-1/32" +/-. This is called an insert bearing, and the outer housing is curved so that when inserted into the flange, it's allowed to self-center.
Here it is in the flange
To replace both of these bearings will cost at least $100 with shipping if you buy them from Toro.
If you search for this bearing online, you will find that a 3/4" inside diameter insert bearing is available, but with an outside diameter of only 47mm, or a little under 1-7/8", which is too small to properly fit into the flange.
Here is my solution. I purchased insert bearings with a 7/8" inside diameter. This bearing has the proper outside diameter of 52mm. I also purchased bronze bushings with a 3/4" ID, and a 7/8" OD. I removed the 1/4-28 x 1/4" set screws, and pressed the bushing into the new bearing. Then I drilled and tapped the bushing, and inserted two new 1/4-28 x 5/16" set screws.
My total cost for two new bearings, which now is a perfect fit for the flange, was $30.00 which included shipping.
On my snow thrower, the outer bearing (closest to the chain) was attached to the shaft with a 1/4" roll pin. Since these bearings only come with set screws, I rotated the shaft so that the set screws avoided the holes in the shaft. There is really no need for a roll pin at that location.
7/8" Insert bearings - UC205-14, $5.63, Bearingson.com
3/4" x 7/8" x 1-1/4" SAE 863 Bronze Sleeve Bearings, #2868T172, $2.51, McMaster & Carr
1/4-28 x 5/16" Black Alloy Steel, Cup Point Set screws, $.11 each, McMaster & Carr
All the prices are plus shipping.
Hope this helps someone to get their snow thrower running quietly and smoothly again without having to spend an arm and a leg on Toro bearings.