Stiches are not sewing straight - will go straight for several stitches & then

Test: With straight stitch and needle on left side sew.
With straight stitch and needle on right side sew.
Does one of the two sew and the other not sew?
The reason is the timing of the needle and bobbin are not set right. In other words it is in need of timing from a repairman.

try these suggestions
Skipped stitches
1. The needle is not inserted correctly
Remove needle & reinsert needle( flat side towards the back of machine)
2. The needle is damaged
replace with new needle
3. The wrong size needle is being used
Choose a needle to suit the thread & fabric
4. The foot not attached correctly
Check & attach correctly

try changing the needle--make sure it the right needle for the fabic
being sewed
also try rethreading the sewing machine top & bobbin
make sure to use every thread guide
make sure the bobbin is turned the right way in the bobbin case
it's also possible that the sewing machines timing needs to be
checked at a sewing machine shop

it's possible that it could be a thread tension or timing problem, when was the last the machine was serviced

This could be caused by several things:

Blunt needle: Have you changed the needle firstly, skipping stitches is a sure sympton of a blunt needle.
Wrong type needle: are you using a regular needle on a stretch fabric, this will cause skipping too, change to a ball point needle.
Timing out: this is the more serious fault, if its skipping after you've changed the needle and sews okay on straight stitch, then it is likely your needle to rotary hook timing is slightly out. Something for a technician to deal with but there is simple diagrams here if you want to take a look at what is involved.
http://www.sewusa.com/Sewing_Machine_Repair/Sewing%20Machine%20Hook%20Timing.htm

You probably have the wrong program setting for the stitches..Check if it is on the correct settings.

that sounds like a timing issue if it will pick up every now and then i would recommend taking it to a brother dealer for repair as timing is not easy to set

hi! this particular problem is common when tension and stiches adjustment does not match and complied to fabrics your trying to sew,there a is hard way to find manual specialy to old ones. but if you want it may help you some i got here on manual sears 1803.if your control look similar to this in figure there are stitch control one for straight stitching and one
on special stitching.the small dial near needle is tension dial.You can set tension on # 3 to 5
stitch dial as in figureif you are
sewing a straight stiches set to # 8 to 12 trial are needed somtimes to acquired smooth sewing,Be sure no mechanical problem regarding in machine operation.try to sew a cotton fabric for trial then if sewing another fabrics sudden adjustment should be done.If your machine is equipted by auto tension just select on the fabrics.well small information can sometime helpfull ...nice sewing

Have you changed your needle? If you have a dull or bent needle it can cause the machine to not lock the stitches together and the result is a straight stitch on every pattern. Also, check your stitch width selector and make sure that it did not get accidently moved.

You can do all of these stitches by using different combinations of your stitch selector, stitch width and stitch feed knobs, for instance, on the panel I can see on your machine:

http://www.jo-ann.com/joann/product/images/52659.jsp?CATID=cat3122&PRODID=prd11333

Stitches 1, 2 & 3 are straight stitches, centered, left and right. Really basic stuff, not different stitches at all. 4,5,6,7 & 8 are zig-zag stitches of different widths. 9 is the widest zig-zag (no. 8) on a finer stitch length, etc...

I think you should try and get an instruction manual for your machine. After a lengthy search of my usual manual sources, I've determined that that this may not be so easy. I think you should contact White on their 800 number and let them try and help you... 1-800-331-3164.

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