I bought this Arctic plow used and don't know the year or model. But here is the issue I have. The plow works good in all directions, but it goes down really slow. Then once the plow is on the ground the lift cylinder won't go down any further (still have about 2 inches of cylinder up). I have left it in the down position and tried to push it down and it won't budge. Before I started using it it would go down all the way, but now it won't go down far enough to get the lift chain off. Not sure if I have air in it, and if I do I don't know how to get the air out. As I said I don't know the plow model, but if it helps it has the pump mounted in the engine compartment.