Based on my previous post, I was wrong. What seemed to be happening with the burner was that it simply was not getting enough oxygen to burn completely. The nozzle that I am using is designed to convert a standard fuel oil furnace to a waste oil furnace. Because the waste oil has a higher viscosity than that of fuel oil (off road diesel), the nozzle relies on compressed air, about 5-10psi, to siphon the oil to the tip. In my initial design, I was relying on the compressed air to add enough oxygen to facilitate a complete burn. I simply added a blower to supply additional oxygen.
I still had some small issues as I believe the blower doesn't move enough air. I had to run the nozzle at 20psi. Anything higher, it would start to blow itself out.
I am also embarrassed with the crudeness of this setup. Remember, it's a prototype...so give me a break. I've begun working on a much more permanent burner.
It's running on a mixture of 25% waste motor oil and 75% kerosene. I was concerned that the oil would flow sufficiently and I would be fitting that in conjunction with the previous burner issues. My plan is to eventually run on 100% used motor oil. Still, it will probably require to be started on kerosene or another easier lighting fuel.
From the time I started the furnace until I poured the half full crucible, it was 1 hour.
