I finally located the bleed Allen screw on my RB1 burner ... But before locating it I loosened another type of grub screw thinking it was the correct one. On the side of the pump there is a long brass hex bar. Right beside that, also on the side of the pump, there is another grub screw (slotted head). It feels like it is spring loaded when I re-tightened it ... and I don't recall unscrewing it as much as screwed it back in. There's still no oil flowing and I'm wondering if this has added to the problem. Any thoughts anyone?

PJS, March 2013

I suspect you have undone the screw valve controlling the oil flow, and just like a mixture control on a carburetter, to set your boiler up again for a clean efficient burn it requires combustion monitoring equipment to get the settings right.
I suggest you get an engineer to service and reset the boiler

GB in Wales, March 2013