Where do I put the oil on my Necchi Model # U229014?

They will only go in one way, they have to be correctly orientated.

https://www.google.com/search?q=Necchi+model+3355+replace+bobbin+case

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Open the light cover
put some sewing machine oil on the long round
thingee, just above the black square
let this set for awhile
then use a chop stick or pencil/pen and push down [gently!!] on the square while pushing the lifter down
if this doesn't help, put a drop or 2 more of oil and let it set awhile longer
or use WD-40 to break it loose and then clean the long round thingee and put sewing machine oil on it

A mechanical machine? How long since it's been thoroughly cleaned and oiled? Sounds like the machine is seizing due to old oil that has dried.

Wheel on right side that controls the needle up and down is very tight...

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If it is the newer Necchi computerized machine, oil ONLY where the manual instructs. The only place that may be safe to oil is 1-2 drops on the shuttle/hook:
How to Oil Sewing Machine

Instruction Manual Necchi 4825

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The following web site indicates the machine should be "lubricated as needed." So, you should probably consult the owner's manual. Your machine is computerized which means there is usually limited oiling required, perhaps the hook.

Necchi 4825 Review Sewing Insight

Be sure to use good quality sewing machine oil recommended for your machine (NOT 3-in-1, WD-40, cooking oil, etc.)

Instruction Manual Necchi 4825

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here are 2 links for a manual for the machine,,you can choose where
to buy the manual from
http://www.sewingpartsonline.com/instruction-manual-necchi-3101.aspx

http://sewusa.com/Sewing_Machine_Manuals/Necchi_Manuals/3101FA_3102FB_Instruction_Manual.htm

here are 2 links for a manual for the sewing machine, one is a
hard copy and one is downloadable, you can choose which one you
prefer

http://www.sewingpartsonline.com/instruction-manual-necchi-4575-download.aspx

http://www.sewingpartsonline.com/instruction-manual-necchi-4575.aspx

3-in-one oil

Oil the machine wherever it needs lubricant

Beldia 1306 - did you ever solve your sewing m/c problem. I have just resurrected my old Necchi and have the same problem, power but very sluggish operation of the needle, could be oil that is needed. Can you help?