I can hear the motor running but it is not stitching. Feed dogs are engaged.

Remove the needle plate and clean the feed dogs with a brush...remove any lint and bits of thread.
A couple of drops of sewing machine oil might help to loosen the feed dogs up. (maybe let the oil seep in and then turn the handwheel towards yourself to help things along.
One other thought:
If your machine has feed dog lowering capability you might want to move that lever/switch back and forth a couple of times.
The feed dogs might not appear to raise or lower, but some machines will only re-engage raised feed dogs when the machine starts to stitch.

Also...verify that the presser foot tension isn't too strong/heavy...and temporarily try using a longer stitch length setting.

Take your presser foot off and the screws out of the plate. Lift the plate slightly and turn your stitch length regulator to the longest stitch that you use. Now set the plate back down on the feed dogs and see if it will sit evenly without binding. Loosen the feed dog screws and see if you can move the feed dogs enough to allow the plate to sit down. Now, retighten the feed dog screws and rotate the hand wheel towards you to see if they will move freely without binding on the plate. If all well, replace your plate screws and then rotate the hand wheel towards you again.

If this doesn't fix it, you may need to purchase a different # feed dog/plate. You might check to make sure that the items you purchased were meant for a Juki. Mostly they will fit different brands but sometimes it is easier to make sure that the combination of feed dog/plate is actually meant for your Juki.

The other thing you can do is to call a mechanic to readjust the machine to make these work (a more expensive option to be sure!). This has NOTHING to do with your timing. If your machine made good stitches before you change the feed dogs/plate. It should make good stitches after you change it. Timing is all to do with stitch formation and not stitch feeding. Good Luck!

Check that the stitch length is set to make ~10 stitches per inch. This stitch is long enough to actually move the fabric. If the stitch length is set too short, the fabric will stay barely move and the needle will stitch almost in place.

Check that the feed dogs have not been dropped for darning or free motion quilting. In this position, they do not rise and are, therefore, unable to contact the fabric to pull it through the machine.

With the presser foot raised and using no fabric, hand rotate the handwheel and watch if the feed dogs actually drop down below the needle plate, move toward the front of the machine, then rise above the needle plate, and move toward the back of the machine. If the feed dogs are moving in this manner, then they are functioning properly.

Is there lint or gunk stuck in the feed dogs? This will restrict the ability of the feed dogs to grip the fabric.

Are the feed dogs worn? Are the little teeth worn so there are no sharp points?

What type fabric are you using? If it is very light-weight or slick fabric, the feed dogs will have a difficult time gripping the fabric. Most machines have a presser foot pressure adjustment so that more pressure is applied between the presser foot and the feed dogs. Consult your Owner's Manual. The adjustment is usually a dial either on the left side of the machine, on the front of the machine located above the needle bar, or on vintage machines it is usually a skrew located under the top lid above the needle bar.

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Are the feed dogs in the raised position and not dropped for darning for free motion quilting? Is the stitch length set to somewhere between 10 to 12 stitches per inch? If the stitch length is set too close to zero, the feed dogs will barely move the fabric causing it sew in the same spot.

Hello Mary Rule
The feed dogs will engage and come up as the first stitch is made.
Happy Stitching
Sewingirl/

When you sew the machine must be set at the correct settings. If your machine won't straight stitch, turn it off at the power point and then turn it back on. Most machines reset to the default straight stitch setting. Secondly when you sew the presser foot must be down. This engages the "feed dogs" or the triangular looking "teeth" below the presser foot. As you sew, the feed dogs grab the two layers of fabric pulling them through, the thread above (spool) and the thread below (bobbin) meet to form the stitch. Finally, maybe fiddling around with dials and settings you may have dropped, or disengaged the feed dogs. Check with your manual on how to re-engage the feed dogs. Hope this helps and happy sewing. Remember, when all else fails..... read the manual.

it's possible that the feed dogs need a adjustment or they need to be
timed by a sewing machine repair technican

It's a shame, but you are discovering why many of us are returning to the old mechanical machines circa 1965 or earlier. The fact is these newer computerized machines have issues far more often than one would think.

If I were you I would call the support line for your machine. Ask directly if your machine has been recalled. And whether or not your motor (never heard of a feed dog motor) or board(s) are covered under the warranty. Ask them to confirm that via email.

Good luck.

there is a couple of things to check:

What stitch length have you got the machine set to? Should be 2.5 for a normal straight stitch - how you set this will depend on the make and model but most machines have some way to adjust the stitch length and width.

Or are the feed dogs lowered? this is sometimes a slide or button on the front base of the machine, sometimes a slide at the back of the free arm, again, it varies between machines. You may need to refer to your machine's manual to establish how this is controlled - you lower feed dogs for things like free motion embroidery so if your machine is computerised with lots of stitches it may even make this adjustment automatically when you choose a free motion embroidery stitch. If that is the case then changing it back to regular straight stitch should return the feed dogs to normal function.

If you raise the pressure foot, and manually turn the flywheel towards you through a couple of stitch sequences can you see the feed dogs raising and falling? If you can't see this happening at all and you are sure that the feed dogs are engaged then it is possible a drive gear in the free arm has failed in which case, you'll need to take the machine to a serviceman.

Did you turn the handwheel? The feed teeth will not come up until the machine is operated. Run it a few stitches and they will come up.