It turned out to be an internal failure inside the Dukes fuel pump that was repaired by CS Aviation under their 1-year warranty. The overhaul cost me $800 but a new pump would have been $1,600. It took about 3 weeks with most of that shipping time back and forth.

My Dukes boost pump also failed recently so I thought I would post for reference if anyone does a search down the road. Mine was overhauled in 2017 by CJ Aviation who also makes a PMA'd replacement to the Dukes pump. The pump had around 250 hours on it and the lower bearing in the pump motor seized up. I sent the pump to Aeromotors LLC in Wisconsin and their turn around was 4 business days. $450 not including shipping is their overhaul price and from what I can tell, they did a nice job with the overhaul and replaced just about everything except the pump and motor housings. Time will tell how it holds up.

Aeromotors just did a pump for me also. Mine was starting to leak a little fuel out the overflow line. Really nice people to talk with over the phone. Turn around time was great! Cost was acceptable compared to what most want. Time will tell the truth. I have talked with a couple other people at my local airport that have used them in the past and had nothing but good things to say about them.