Take a good look at your coolant bottles to make sure the cap is not cross threaded or stripped. This happened to my sled this weekend and it lost coolant and ran hot. This was in the early am so hard pack with little dust didint help. I got it to a dealer in Eagle river,by adding Lipton Brisk Ice tea and marsh water,didnt have to resort to pissin in the bottle. and they fixed it in less than a hour and I was back on the trail.The problem can start with the dealer who sets it up or the factory not getting the system bled of air properly and they can get hot and warp the coolant bottle also.They also recommend a longer snow flap of aux heat exchnger in the rear.