I thoroughly cleaned Nora last weekend.
I took out all her old oil using rubbing alcohol, applied with cotton swabs and an eye dropper.
The more I removed, the more I decided to dig for more. I took off all plates that could be removed with a screw driver.
The high heat from a hair blow dryer was handy to help loosen extra stubborn oil spots.
After cleaning, I used a specialty oil recommended by the Necchi Yahoo group: Triflow Teflon oil. This oil is amazing. You can find or order it from bicycle shops. Be sure to get the teflon (P.T.F.E.) and do NOT buy the spray.
I used the Triflow at each moving junction, being careful to NOT over-oil. One or two drops is all that is needed.
After just one application, a stuck feed dog drop lever started working right away. I had used regular sewing machine oil available at sewing stores to no avail the week before. Removing that oil with rubbing alcohol and applying Triflow, fixed the problem.
My frozen flywheel is starting to move. I think I should point the hair dryer at it for a prolonged time period. The great thing about Necchi's is that frozen parts can be worked with and fixed with a bit of patience. The machine is in working order with the frozen flywheel - it's just that the main shaft does not disengage in order to wind bobbins without the needle moving.
Don't be afraid of vintage machines. The working mechanisms are fascinating.
Here are a few photos of the machine innards cleaned prior to applying the Triflow.