I had the same issue once, and I guess it is pretty common, pull your filter off the oil reservoir and replace it or blow it out with an air compressor. if still no love, pull the tank and test the pump. I hooked a 12v deer feeder battery to mine to test it. wound up rewiring the whole thing and it worked fine.
if still no love, drain the oil tank that is on the motor, this will trip the little float switch telling the remote oil pump to come on. if that doesn't happen, test the float switch with a meter. that about summs it up....I think