This article was submitted by HiloET4 (Robert). It summarizes the task of replacing a flywheel and stator, on a modern Vespa.
I've had a '01 ET4 since new. About nine months ago the motor stopped. I assumed it seized since the oil might have drained towards the rear while the front was jacked up, and didn't make contact with the pick up. I started to get into it back then but said, I'll ride my motorcycles instead.
Well, last weekend I got into the wrenching mode and tore into it. It turns out the Stator had self destructed, and pieces of the magnet bound against the flywheel.
Pic of a magnet chunk (look at about the 1:00 O'clock position and in the vents):
Special tools required are the Flywheel Remover/extractor part # 19.1.48564, a Impact Driver with cross tip screwdriver is handy, a 18mm socket (not that special but I got a ton of tools (my father was a television repairman) but I don't have any 18mm sockets or box wrenches). Other handy items include a torque wrench, motorcycle jack, "Shorty" type metric ratcheting box wrenches, 1/4" drive metric socket set with extensions, and a headlamp (never went and got mine but I sure wished I had on many occasions).
Flywheel Remover/extractor part # 19.1.48564 ready for action:
Flywheel removed showing the fragged flywheel magnets and tweaked stator:
Old and New side by side, the old cut thru the wiring harness:
Noob stator in place:
Flywheel in place:
And all Pau for that operation.
Other lessons learned
- Power pack removal is straight forward, just make sure you hit all the items listed in the "Service Station Manual"
- Don't forget to take off the sparkplug cap.
- I used Dielectric "Tune-up" grease on all of the electrical connectors during re-assembly.
- I'm thinking the whole job can be done W/O removing the motor, but then I pulled mine 'cause I thought the motor had seized...
- Find all the torque settings, and write them down before you start re-assembly. I didn't, and leafed thru many pages trying to find the ones I needed.
- You don't need the flywheel holder apparatus if you put a block in-between the teeth of the front pulley and the engine casing.
Anyway, it's on the road again... Ride safe, Robert.