I have a Case 885 and have had temp/overheating problems. I thought I had it fixed until today. I have replaced the radiator, temp sensor, temp gauge, thermostat and belts. We have been running it cutting, raking and baling hay for the last 3 weeks. The tractor temp will stay at about 220-240 all day. Today we ran it for about 5 hours cutting hay then stopped for a break for about 15 minutes. We started again and after 20 minutes it started steaming and releasing water from the radiator cap and drain hose. After it cooled I noticed the steam was hot enough to melt the rubber on the cap. Why would this happen and what can I do to fix this?