This summer an 824 came up for $100 because it was broken and I bought it as a fixup . The unit would not go move forward because the drive sprocket teeth on the hex shaft were touching the teeth of of another gear on another shaft.
The transfer setup power is this. The hex shaft carries the friction disk and a small gear which drive a chain. The friction drive plate is moved forward by the hand control. It presses against the friction disk on the hex shaft, rotates the hex shaft and turns a small gear and chain. The chain drives a large gear on another shaft which through other gearing turns the wheels.
It turned out that the hex shaft support bearing had worn and the shaft so loose the drive gear on that drive shaft meshed with the teeth of the large drive gear on the traction drive shaft and the chewed the teeth of the large gear. The warn flange bearing caused the traction drive problems because it was worn, enlarged enough to create slop.
The large gear, drive chain and both flange support bearings were replaced. After light use this winter the snowblower was not moving to fast in forward and slipping in reverse. It turns out the flange bearing is worn again and the hex shaft so loose it does not keep the friction disk drive wheel in place with good pressure when the drive plate goes up to drive it.
The rig will go forward and barely backward but in a another week of use the flange bearing will be warn enough it won't move at all. The shaft will be so sloppy on the flange bearing it will not provide support when the drive plate is pressed into the friction disk.
The flange bearing is not a roller bearing. The internal part the bearing is called powdered metal something. It not solid metal or a roller bearing. It is powdered metal bonded with something to form a round internal section something like half of an egg with a hole for the shaft end to ride on. The hex shaft the friction disk rides on is the flange bearing of powdered metal. The egg shape powdered metal part does not rotate with the shaft. It stays in place and the shaft rotates inside the powdered metal part of the bearing. The hex shaft fits into the flange bearing with a loose fit so just rides on the powdered metal part of the flange bearing. This does not seem like a great arrangement to me but the Toro repair place says they do not see that many flange bearing repairs. They say my quick wearout is very odd.
The powdered metal part inside wearing out quickly may be my fault by using the old hex shaft and not buying a new one. It may have been rough and chewed right through the replacement flange bearing powdered metal again. I am not sure of the condition of the end of the shaft when I replaced the flange bearing. It's now very rough and will eat right through another replacement bearing.
Here is the question.
I would like to replace the powdered metal flange bearing with a flanged roller bearing. I don't know about bearings and looking for advice if this is a good ideal or other alternatives. A few net searches show some flange bearings with set screws to keep the shaft locked inplace. The original design seems hoaky to me. The shaft supported in powdered metal does not seem so great and if I replace both again I think the powdered metal will just wear again. I'm suprised Toro uses such a crummy setup which I would think would wear out quicky but the Toro guy claims he does not have a big call for those parts. Any suggestions?
The pictures show my bearing and possible replacement bearings.
This message was modified Feb 10, 2008 by trouts2
