Disengaged. My sewing machine fell and now the motor works but it doesn't work the needle. Is there something that comes apart when if falls?

Question edited for clarity.

It can't have come far and they can only fall downwards. Open the end and look for a threaded hole.

https://www.google.com/search?q=SB1818+sewing+machine+manual

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change ur needle bar and also check needle size before insert in it.

this is all i can find so not sure if it will help you out... Fixing common sewing machine problems Brother Sewing Machines Europe GmbH ..or this one... Beginner Guide to Sewing Sewing Machine Parts Reference Guide ..or this... E6 ERROR

If your machine is mechanical (NOT computerized), this link may be helpful:

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

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I don't know this make but if it is NOT electronic you could try using a magnet to remove whatever fell in. Or turn it upside down and shake it out. Sounds like it is stuck in the mechanism.

Have you pulled apart the bobbin race area and checked for any bits of broken needle?

Is the clutch disengaged on the flywheel?

Otherwise, was the loud cracking noice coming from inside the machine case in which case it could be a gear internally that went and the needle breaking was just the result of this, in which case, time for a road trip to the service tech.

needs a new needle clamp screw & possibly the needle clamp too

try sewingpartsonline.com

Check your bobbin winder lever, make sure that it is fully disengaged.

That can be tricky. Some thread guides and needle clamps have to be assembled and then slid up into place with the needle screw holding it together. Some have a set screw to hold it.

Number of possible causes. First thing I would check is the timing, impossible to describe how to do it, sorry I cannot help anymore