How do you and location to lube this machine - White Sewing 915

How long since you've had the machine cleaned and lubed? Sounds like perhaps the selector mechanism has seized. I know this is a common issue with the older Bernina (Records) that require frequent cleanings and oiling (with good quality sewing machine oil or Tri-Flow Synthetic Lube).

Depends on your machine... If it's a computerized model, best to follow the instructions in the owner's manual.

If it's a mechanical machine, the metal moving joints could use a couple drops of good quality sewing machine oil (I use liquid Tri-Flow Synthetic Lube).

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

Yes, most likely the mechanics are seized due to old oil that has dried. I have a 930 that I frequently clean & lube thoroughly to keep it running smoothly. The only thing is to stay away from the basting stitch mechanism (sorry, can't remember if your machine has it) located in the middle of the needlebar directly behind the take-up lever. Once you give your machine a good lube, you'll be amazed at how quietly and smoothly it runs.

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

Here's a Service Manual for your machine:
https://www.manualslib.com/manual/1059902/Bernina-1030.html#manual

Only a caveat, but is generally recommended to NOT use compressed air to clean sewing machines. Frequently, it pushes the lint and dust further into the machine so a technician will have to clean it.

Sears carries manuals for their products.

The Kenmore that I had, takes the needle with the flat side facing the back of the machine. Then the needle is threaded front to back.

You machine is an oldie but "goodie." Make sure you clean and oil (only fresh good quality sewing machine oil or Tri-Flow Synthetic Lube) 1-2 drops every place where metal rubs against metal. Open the top, the area where the bobbin is located, and the side covering the needlebar. Gently rock the handwheel and watch where things move. Do NOT oil CAMS, plastic/nylon gears, or belts. Oh, don't forget to move the dials and levers and lube those too to keep them moving freely. Do this every 40 hours or so of sewing (or after it has been stored or unused for a period of time) and your machine will serve for many more years. If the machine starts laboring or seizing, it needs TLC.

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Ooh, do not use WD-40 or old sewing machine oil. WD40 will work for a short time but turns to gunk quickly and just add to the current problem. The old oil has solidified and turned to glue.

Pick up some liquid Tri-Flow Synthetic Lube (hardware store or bike shop). Apply 1-2 drops every place that metal rubs on metal. Do NOT oil belts, synthetic parts, or tension disks.

Then direct heated air from a handheld hairdryer into the internal mechanism. You may have to repeat alternating lube and heat. If the oil has solidified and seized, this activity should loosen it.

In the future, be sure to keep the machine cleaned and lubed (even when in storage). An overlocker requires more frequent lube since it stitches so much faster than a sewing machine. If you want, you can pick up oil that is especially for sergers--it is usually a lighter weight than regular sewing machine oil.

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Seems you need to clean and lube your machine. remove the top and bottom cover cover open the front cover brush out all lint check bobbin for thread lock and lint. lube all moving metal parts with "non petroleum " light oil. Do not lube plastic parts unless there is apparent fiction. " DO NOT USE PETROLEUM BASED LUBRICANT " as it will dissolve or soften plastic parts!

your machine needs service. Likely the motor and insides need to be lubed/oiled. Take it in for "Clean, Lube and Timed"

If this is a 2000, 5000 or 6000 series Husqvarna Viking, you have not cleaned the reverse mechanism fully. It will come loose when completely cleaned and lubed.

Put some spray lube on it or oil at the pivot and that should take care of it. Make sure the switch is making good and clean ,might want to spray that as well. Try and do a dry lube cause liquid lubes attract dirt.

the machine needs a full service, which you can do yourself if you are confident removing machine covers etc. oil all moving joints and shafts through sleeves and wind by hand to work lube in.

otherwise see a tech for a service.

scott