I have a Bro PE 400 D. The feed dogs do not seem to be pulling the fabric through without me pulling on it. Stitches are very small even when put on a longer stitch. Embroidery Unit works fine.

Hi
Try to clean the feed dogs aria
Check the screws
Add foot pressure if needed
Thanks

Sewing machines have feed dogs to pull the fabric through the machine. They are usually a pair of metal teeth that are situated in the needleplate and press against the presser foot. They grip the fabric and pull the fabric under the presser foot as the needle stitches.

You can find the drop feed dog instructions in the owner's manual:

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0ahUKEwjgj8_ggZrPAhUr4oMKHZ5CBrwQFgghMAA&url=http%3A%2F%2Fjanome.com%2Fsiteassets%2Fsupport%2Fmanuals%2Fretired%2Fembroidery%2Finst-book-mc9500.pdf&usg=AFQjCNG-le_VN0TN14xsUNRpA9ylXPz26g&cad=rja

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How close the stitches are to each other? Stitch length?

There is a stitch length selector on your sewing machine. The owner's manual is the best source for information. Technically, the stitch length selector increases the movement of the feed dogs. The feed dogs pull the fabric under the presser foot. Increase the stitch length, the feed dogs increase movement and pull the fabric through faster.

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***Your feed dog under the pressure foot seems to be pulling on one side a little harder which indicates wear. It is likely to solve the problem by replacing the feed dog.
***Before you do this try to lower the pressure on the pressure foot. If the material you are sewing is thick it will have an effect on the pull of the feed dogs. The material you are sewing that you sent appears to be jeans material. It looks like it is thick and somewhat slippery.

I think you are saying no stitch is formed also referred to as the needle not catching thread. Below offers a variety of diagnoses and solutions which are straight forward.

Sewing Machine Needle Not Catching Thread

Below is general advice quoted from 6 common sewing machine problems solved:

Skipped stitches are usually due to a bad needle. The needle may have become damaged or bent by sewing material too thick for the needle, forcing material through the feed dog, or hitting a straight pin. If the problem seems to be consistently reoccurring, it may be due to forcing the fabric. Sewers should allow the feed dog to pull the fabric and only use their hands to guide the fabric through the feed. When sewing knitted fabrics, using a stretch needle can help prevent skipped stitches.

Below is a video showing how thread is hooked into a fabric:

Sewing Machine Anatomy How Stitch is Made

What is your stitch length? I have always followed the rule... Bulky/Long stitches, Fine/Small stitches. If you have a "walking foot attachment otherwise known as an even feed foot..you might give that a try as well.

Presser foot tension is to low for the weight/finish of the fabric, or bottom dogs are worn.

• The feed dog feeds the fabric under the presser foot while you guide the fabric.

  
  

• The feed dog regulates the stitch length by how much fabric passes under the presser foot as the machine stitches.

  
  

• It is important for you to not push and pull the fabric under the presser foot. Allow the feed dog to move the fabric, so that you do not bend and break sewing machine needles.

Hope this helps.

You need to be using a free motion foot or a darning foot, the regular presser foot is not for free motion.

The embroidery carriage automatically lowers the feed dogs when put in place

The fault is with the height of the feed dogs it is an internal adjustment that you tech. should make. As a guide if you cant see the majority of the front teeth above the plate or feel them with your finger then they are to low and need to be raised. Also check that the pressure of the sewing foot is set in the right position on the left side of the machine.