Stuck flywheel bearing

Emailed my mentor Mike A.

Mike,

I am working on the fly wheel bearing. Heat gun got it piping hot. I tapped the housing on a wooden surface and bearing moved a little. Reheated and tapped against wood again. No movement. Stuck in place. Used a 24mm (my largest) socket to tap it out. It went to the end is just sitting there. Won't move further. Of course the socket bent up
the metal plate behind the bearing. Crap! I will need to replace that. I will try to reheat yet again and repeat the process.

Jeremy

Mike's response:

"yep you stuck the bearing. I said I use a propane torch for a reason, the heat gun just won't get things hot enough to work right. Actually I've had good luck using MAPP gass which burns even hotter than propane but requires a little more skill to not ruin anything.

Here is how you fix it.

Use a propane torch. Cheap to buy from Home Depot or Lowes (any hardware store really)

Heat up the mag flange. Move the torch around the flange to keep the heat even.

After about 5-7 min it should be ready to go.

Now carefully tap the bearing back home, you need to free up the jam. BE VERY CAREFUL HERE, the outer part of the flange around the bearing is very thin and can easilly snap off making your mag flange in to a paperweight. Sometimes the bearing will drop back in to place but not usually.

Turn the mag over so the bearing will want to drop out, over a coffee can works well, make sure the bearing/flange is level!!!. I use my big vice to support the mag while I heat it up.

Keep heating the flange up. After about 5 min if the bearing hasen't droped out on its own then try to tap it out. You want to use a socket thats just smaller than the outer hole on the mag so the seal can EVENLY push the bearing out. If I remember right a 27mm works well (and is the same for the rear hub nut).

Things are going to smoke (a lot) and be really really hot so don't touch things with out gloves or pliers. Once I get the bearing out I like to set the mag flange (or case) aside on the garage floor out of the way to allow it to cool down. Once it's cool clean/degrease it.

Getting things back together are harder and take a bit of patience to do right and not melt the seal. You might want to have some one with some more expierence put the bearings in for you to stay on the safe side. I can do it but it might be a pain to get the parts here, it would be easier to call Barry at SF scooter center.

If you want to send the parts to me I have time to do the job. Next day turn around." - Mike

Next step: I requested and received a free propane torch from Freecycle.org and now need to get a 27mm deep socket.

Follow-up email to Mike:
The damn propane torch kept blowing out. Used the heat gun again. The hole mag flange was hot even through my gloves. I had to tap it back in a little. I borrowed a 27mm socket (a 28mm or 29mm would have worked a little better) from a neighbor. I had to tap it moderately hard to get it free and to pop out. Of course I destroyed the track on the bearing, but since I am replacing all bearings this isn't an issue. Come to think of it everyone I speak to says to always replace the bearings when restoring. Silly not to. Again, I did destroy the metal plate behind the bearing, but I suspect I can buy one of those for a few bucks. I used the coffee can idea and it worked. The bearing was really stuck in there. I wiped it out and the inside of the mag flange looks to be in good shape. The bearing I took out was engraved by hand with ZS something and a C3 after it. Is that factory stock?

By the way, FreeCycle is where I got my propane torch. Not bad.

Two more bearings to go and not much more is left.