I have a New Holland Powerstar 4.75 that seems to be developing an overheating issue. I have about 250 hours on the tractor and it was serviced at about 175 hours. The last couple of weeks, while pulling my 15 batwing through thick grass (mowing at about 2.5 mph), the engine would approach the red-line on the engine temperature gauge. After a few minutes of idling, the temperature would drop and I could resume mowing for about 15 minutes before having to idle again to allow the engine temperature to drop. I was knocking out the dust screen about every ス hour or so and it wasn稚 too dirty between cleaning. The radiator and reserve are full (filled with antifreeze). I知 outside Houston and it was hot and humid outside (mid 90痴 with +100 heat index). I didn稚 have this issue last summer. Do I need to flush and/or rod out the radiator already or is this an issue with the New Holland engines?