OK I did a search found nothing on this topic... I have a 13 259b3 w/ 1000hrs on it just started having issues with my coolant over filling the overflow container, so far Ive refilled my rad and put it back to work for about 45 minutes and I noticed it started to fill back up again and the rad indicator level showing low again, first thing that came to mind was my head gasket so I checked my oil level its good with no coolant I checked the coolant for oil its ok and running it doesnt show any signs of burning coolant. Any ideas on what it could be ive just bought a new rad cap gonna try that first but could it be my thermostat stuck closed ??? and could someone tell me which way the coolant flows left to right or right to left i noticed it was hotter on the right side but I thought it flows right to left.. over heating light has not come on once OR???? do i have a nasty air lock and what have you done to fix it thanks in advance