Serger to "quilt" a quilt?
 

Just wondering if it can be done..I don't have a walking foot.

Sorry...I know it can't be done because of the loopers. Just not thinking clearly:)

https://m.youtube.com/watch?v=nAzqq98Q0KI

The above link goes to a Nancy Zieman sewing video where she uses a serger in quilting.

You can't really quilt with a serger but the serger can be used to do kind of a quilt as you go quilt, using strips of fabric and batting. See this tutorial: https://m.youtube.com/#/watch?v=YdONf2oaQM0

Google serger quilt tutorial and there should be video tutorials.

Use an darning foot and set your stitch length to "0"

I agree with Brenwalt. With a basic straight-stitch sewing machine, you can do FMQ. With enough practice, you'll even learn to quilt straight lines that are marked... or, on some machines you can buy a ruler foot and acrylic rulers to give you a very straight line.
A darning foot is available 3rd party usually for under $30. Much cheaper than a walking foot!

One can "disable" the cutter on some sergers - and make sort of a decorative stitch.

I don't think it would be very easy to do on a quilt, though.

A serger is an edge finishing machine. It's not designed to sew in the center of a flat surface, such as a quilt.

Most sergers can have the cutter disabled, and I believe a decorative type stitch can be made if you fold the fabric and treat the fold as if it were the edge. You sew a narrow or wide stitch, (only use 1 needle on top) then unfold the fabric and pull on it to flatten out the stitching. I haven't used a serger in ages, or tried this, but I understand you can use specialty threads in the looper for effect.

A Coverstitch machine looks very similar to a serger. You can quilt with it. It does a single chain stitch, and and double and triple coverstitches. It does not cut fabric.

If you look at the hem of a purchased T-Shirt, that is a cover hem stitch.

I've done decorator on curtains with the chain stitch and King Tut varigated thread.

Those off the edge can be done with a serger. I've used some for heirloom, and you can blanket stitch by using a tearaway stabilizer.

The coverstitch can do the middle of the block.

I got my first walking foot at Joann with a coupon for $15.