Needle thread will not pick up bobbin thread

If you are saying the top thread does not pick up the bobbin thread, then the needle could be damaged (replace with a brand new needle) or the machine was knocked out of time. Search for sewing machine timing or take it for service.

Be sure to use a brand new needle because a bent needle could miss the bobbin thread.

Search the internet for sites and videos relating to sewing machine timing or take it for service.

First thing to always try: Install a brand new needle. A dull, worn, or bent needle will cause great frustration. It is also the least expensive resolution to most problems.

Second: Remove all the threads. RAISE the presser foot. Rethread from the beginning making sure it is threaded correctly.
Pull up the bobbin thread before beginning to stitch and hold the thread tails in the left hand while slowly taking the first few stitches:

How and Why to Bring up the Bobbin Thread

If still having issues with not pulling up the bobbin thread, the needle/hook may be out of time.

Sewing machine won pick up bobbin thread hook timing fix

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Try installing a brand new needle. Use a different brand of thread.

All About Needles

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1st: what type of sewing machine? brand?
2nd: it's not picking up the bobbin thread and jamming up because it's out of time.
the machine probably skipped a tooth on one or more of the gears and the gears need to be either replaced or re-timed.
either of which can be very difficult for the average person. your best bet is take the machine to a repair shop or buy a new machine.
this picture is for timing a standard Kenmore type machine. also works for some Singer machines.

remove bobbin and reinsert. Re thread needle . Make sure the right size of needle for the material. And check that there is not a wad of fluff under the feed dogs.
Best wishes

Remove the bobbin and case from the bottom. Try dusting it out and add a little oil. Also, check both top and bottom thread tensions. If that does not help then you may have a timing issue which requires a lot more technical expertise.

the looping on the underside sounds like a needle thread tension problem. 1st off check top (needle) threading then turn machine by hand to pick up bobbin thread

Hello,

You can take the slide plate off, that your needle goes through and watch to see if the arm grabs the bobbin thread, if you can get it to pick up, than slide scissors or something flat under your needle and manually pull both threads through, replace the plate.

Your bobbin thread could be wound to tight or spliced threads on it, and your tension needs to be adjusted. If your using a pedal, try setting to a slower speed.

I would try a different bobbin and thread it manually as in the step I mentioned, if you can't see the arm grabbing it, you will need to check to see if you have loose threading jammed in youir machine, if this isn't the case and adjusting the tension dosen't help...than you will need to replace the bobbin casing.

Kind regards!

check your needle to see if it's bent---roll on flat surface to see if it roll correctly
on some sewing machines when the thread comes off the thread take up lever it can cause the machine to jam
also if the bobbin thread becomes tangled it can jam
check the bobbin area for lint or loose threads
try having a top thread tail & bobbin thread tail of 3-4 inches
try holding the top thread tail & turn the handwheel on the right side on the machine manually & put the needle down into the bobbin area & see if the bobbin thread will pick up that way