I have an old singer zig zag 457 sewing machine that use to work fine, but now needle wont move

Does it straight stitch with a zig zag foot? Go back into the menu and clear everything then go to straight stitch, then press the little buttons beside the Zig Zag dial to position the needle left or right

The machine has probably seized due to lack of regular cleaning and oiling.

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

Have you changed your presser foot over to the zig zag foot? On some machines it won't work correctly until you change to the correct presser foot.

Joe, you might try a larger needle than you're using. You might also want to try a larger leather needle. You machine should take needles up to a size 18.

It sounds like the needle you're using is having a problem picking up the bobbin thread, and that might solve it.

try a new needle--one for the fabric being sewed

could be a problem with the cam that does the zig zag, you might need to have the machine checked

if your sewing with light weight fabric also try using stablizer

Hmmm sounds like an issue I had/have with a singer stylist. There is a knuckle part that connects the zig zag mechanism to the needle bar. Mine had a pin that kept slipping out. When I took it apart (and lost the pin) I also discovered that the "round" holes the pin went into were work out and were more like ovals. The machine is now a parts machine.

if you bought the machine used, then it's possible that a
cam or gear is either worn or damaged. & needs to be check at a sewing machine shop.
if the machine is new,,then take the machine back to where you
bought it & tell them about the zigzag, even let them try it & see
what happens, I been sewing for over 30 years & I wouldn't keep
it,, if you bought it new,, I'd get another one

There are manuals avilable online to purchase for the singer machines, SOrry I was not able to locate a site that has them for free.
.... http://sewingonline.co.uk/singer-manuals.html

Did you switch the metal plate to one of the ones that won't allow left/right movement by any chance?
If the wrong plate it in -The machine somehow figures out that the plate won't allow the needle to move in the left/right directions and only does a straight stitch or funky other stitches.

Over time, and especially when not used, there is a likelihood of dust and old oil forming a sort of glue, or clag....

Remove the needle for safety, then, when you have the setting on Zig zag, gently push the needle arm to the opposite side of the zig stitch.......release the needle arm, and if it springs back quickly, it is fine, if it moves slowly, or almost not at all, then the clag needs removing with application of few drops of methylated spirit to start, at the sort of piston affair that shifts needle arm L & R .....move the needle arm back & forth until it frees up, a drop of oil to finish.........if almost seized, may require leaving overnight after using a penetrating lubricant if it is really resistant....I have had them on the bench for 3 days with manual manipulation a few times each day before they finally come good.

Denatured alcohol is fine, surgical spirit too, different countries have different names or products, essentially alcohol with few impurities that will evaporate quickly with little residue.

Hope this does work for you, tho' as I said, it may take a little time to penetrate depending on severity........the same applies to the reverse mechanism of many machines when they seize.
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