husky 55 not oiling chain?

I have taken the bar off, the silver cover over the oil mechand taken the oiling worm off. It is not worn at all, I have emptied the oil tank and put petrol in to clean it out. The petrol came out of what looked like a breather hole instead of where I think it should come out when the silver cover is on. I have cleaned the bar and removed all the gunk from the oil hole and it is still not oiling.