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.

Day 1 -- Engine Disassembly

Issues:
- Some casing studs came out with the nut.

- At least one of the threaded holes in the casing are shot. Heli-coil?

- The kickstart lever was welded on.

- The crank and flywheel are frozen together. I don't have a flywheel remover tool yet. I hope it frees easily. I will post more on this issue later.

I will document the remainder of the disassembly and post a second slideshow for that.

Yes, I know there is a Vespa sign hung. My wife owns a 1967 Vespa SS180. A Lambretta sign will go up as well.

Note: I do not have a clutch basket holding tool, so I used a creative approach. I used a piece of wood to lock the basket and spider. I tapped the wood in with a hammer. My thought is the wood is softer than the metal and would not damage it. I then hit the screw with a impact wrench at the lowest setting just punching it for less than a second each time. Nothing moved so I stepped the wrench up to the second setting and repeated. Again nothing. I stepped it up to the third and final setting and hit again and it broke the nut free. I never fired for a full second in length with the impact wrench. It was fire and immediately release and repeat.

Lessons learned:
"One thing, never try to remove a clutch without a clutch holder. The centre basket (spider) is really soft, and almost impossible to re-align if you bend it. Hopefully yours will be OK. I bent a couple, before I realised it was cheaper (and easier) to use the proper tool.

Your flywheel should come off easily, but remember to put a new woodruff key in when you rebuild. They're cheap, so it's probably worth to have a spare." - Jim

Parts Ordered #1 for engine rebuild

Below is my first parts order for my engine, which I ordered from Scooters Originali.  I did not include the quantities below.

Spacer, Seal Retainer - Mag

Screw, DriveSide Oil Seal Plate

Oil Throw Washer A16

Deep Nut - 8mm

Kickstart Rubber Bumpstop

Cone Engine Bolt - Li Special/TV/SX/GP

Washer-Engine Bumpstop Rubber

Engine Rubber Bumpstop

RIV Bearing- Rear Hub Bearing RIV

Kickstart Pad - Ser 3 - Black

Spacer, Bearing Spacer - Mag

Washer, Split Lock - 7mm

Flange - Rear Hub Seal Holding Plate

Distance Nut Spacing Cylinder Cover - 8mm x 30

Nut - 7mm Jam

Seal Set - 5 Engines Seal ROLF

Main Jet - SH / Pilot PH - 106: SH1/20

Engine Mount (Silent Block) - Large
Ser 3 Special/TV/SX/GP - TUTTO (Sold in
Pairs Only)

Grand total: $188.12

Note: I spoke with Gene M. Tutto used a "blue" mark for TV and "yellow" for GP on engine mounts. Tutto says they used different hardnesses for the rubber in these two mounts, but Gene questioned if Innocenti really went through this hoop on the stock mounts. He and other reputable shops have used the GP mounts on Li/SX/TV and had great results.