We have a Hitachi EX300 LC and there is oil getting into the antifreeze causing a sludge and causing machine to heat up. We replaced the oil cooler and gasket but we are still having this problem!! Anyone have and suggestions what this could be? Thanks John
is there antifreeze in the oil as well? I would think maybe head gasket
I had a similar problem in the past. and I could not see any evidence of coolant in the oil until I pulled the plug. When I cracked the oil drain plug after the machine sat over night; the first thing to come out was coolant.
Your problem is the water pump. On the Isuzu engine there is a bearing that is lubricated by pressure oil. Your oil pressure is greater than the coolant pressure when the engine is running and will contaminate the coolant. When you kill the engine, leftover pressure in the cooling system can force coolant into the engine oil. Here's another thread on the same issue: HeavyEquipmentForums