This has been the most difficult thing so far. In reading about other people’s experience, it seems wheels and bearings both upper and lower are hit and miss. My lower wheel wasn’t too much of a struggle, but the upper wheel was a disaster.
I couldn’t remove the wheel from the shaft. I wound up using the large gear puller (of the set of 3 I purchased at HF, mentioned in a previous post) to remove the wheel from the shaft. Even with the puller it was a bit difficult. It was really stuck on the shaft tightly.
But the fun was just beginning here. Next was bearing removal. There are two bearings inside the wheel hub. I read instructions on the removal but didn’t comprehend exactly what was being said. Instructions indicate tapping on the top side of the bearing with a screw driver or punch to remove it from the bottom. I tried to pop the bearings out by banging on the bearing on one side to pop the bearing on the other side free. The instructions said to use a screw driver or a punch. So I was banging away on the bearing to no avail. I tried using larger dowels and things that I would allow me to cover a greater surface of the bearing I was banging on, figuring the straighter down I can push it, the easier it will be to pop loose. I started to use the gear puller to push them through, but it just seemed like it was going to stress the wheel too much and I’d wind up with a bent wheel. After much frustration at doing this on both sides, I realized that the instructions were saying was that you had to tap on the top side of the bearing you were actually trying to remove. In order to do this, you have to insert the screwdriver or punch inside the center hole of the bearing and try to catch it on the miniscule rim of the bearing that is inside that hole.
So I set about banging on that and not really catching much of an edge on this hole at all. I googled it for youtube videos, of which I found none. I finally found a post on a forum somewhere that said that you could put a 1/2” down inside the hole and then angle it a bit to try to “grab” at the lower bearing then tap on that dowel to try to free it. I used a socket that had a 1/2” o/d and it finally seemed to be doing something. What ultimately happened was I got the slightest little bit of the bearing to move. Between the two bearings is a spacer. This spacer is a cylinder with an inner diameter that is the same as the inner diameter of the bearings. But it is just a cylinder, so its outer diameter is just a fraction of an inch larger than the i/d. After getting the slightest movement out of one of the bearings, this cylinder started sliding around inside, allowing a little more of an exposed edge of the bearing to rest the punch/screwdriver/whatever on. I shifted it around and tapped a little, shifted the cylinder some more and tapped some more. Did this around and around and around and finally got it to pop loose. I flipped the wheel over and with one bearing out, the other was entirely visible, so I used a large socket to pop it out. Again, with great difficulty. These were really jammed in tight.
Something else the other posts I read said was not to bang on the wheel very hard. Just use light taps so you don’t warp the wheel. I may have warped the wheel. Will have to wait until I mount it again to see how it goes.
Below is what the inside of the wheel hub looks like with the bearings and spacer cylinder removed. You can see these clips in place that prevent you from popping the bearings all the way through in one direction.
After removing the bearings, I cleaned up the inside of the hub with some WD-40 and a light sanding/scouring. I cleaned it up with a paper towel and applied a light layer of 3 in 1 oil on both the inside of the wheel hub and the outside of the new bearings.
I used the same approach to inserting the new bearings as I did on the lower wheel. By lightly twisting them as I inserted them to minimize any angle. I still managed to get a slight angle on it and was able to press down the high points with my fingers. I only seated them maybe 1/16” and then used a wide-jaw clamp with wood blocks as pads to press them evenly into place. Due to empty space inside the wheel hub, my biggest concern was that the cylinder/spacer would tip over after pressing the bearings in place, effectively blocking the holes with no way to unblock it without tapping the bearings back out again. As it turns out, this is exactly what happened. I was able to set it back up which I believe is also an issue. As I have the bearings pressed flush with the outer surface of the wheel and the spacer is still just loose inside (loose enough that I can tip over and set up the cylinder/spacer). It should be pressed between the two bearings and be held firmly in place. I’m concerned I may have received the wrong bearings (not deep enough to adequately fill the wheel hub). We will see. In reading other resources on this, it sounds like once this is mounted to the shaft, the tightening of the nut will draw everything together.
Below is a photo of the wheel with the new bearings in place. The bearings are pressed flush with the outside of the wheel and you can see the edge of the spacer/cylinder, not aligned with the hole in the bearing.
I put the wheel back on and tightened everything up. There was an extra shim (smaller than the shim for the lower wheel bearing) that fits the upper wheel shaft. I used it between the outer bearing and the wheel before mounting the wheel back on. When I tightened up the nut, I could hear some more movement of the bearings being pulled in, but not much. I spun the wheel. It seemed to run smooth. I tightened a bit more and it slowed down, so I loosened just a touch until the wheel spun freely again.
I also had some time to go ahead and disassemble the entire upper portion of the saw. I removed the back cover, the tension assembly and upper guide assembly/thrust bearing/etc.
One thing I scratched my head on for a minute was how to remove the back cover. As someone who has never taken the back cover off of an old Delta band saw before, I wasn’t sure. There were clearly two points of attachment, which are the bolts that hold the front cover on. But I wasn’t sure how these bolts were attached to the main frame of the saw. The bolt on the right didn’t turn in either direction. I didn’t want to take a wrench to it and force it if that wasn’t what was supposed to happen. With the lower thrust bearing, there was a sleeve over the bolt that was holding the bearing in place. These bolts do appear to have a sleeve, but I couldn’t get the sleeve to move. So I tried messing with the bolt on the left. It unscrewed quite easily (counter-clockwise to loosen). I did the same with the bolt on the right and the back cover came right off.
Below is the screw on the right after having already removed the back cover.
I replaced the tension spring as well, which is so easy it isn’t worth describing.
Hopefully this weekend I’ll get a chance to clean up the remaining parts of the upper guides and get the upper thrust bearing replaced.