Last weekend I stripped around the top end to check my valve timing. And found in the oil hoses from frame thick, white gloop. I'm thinking head gasket leak. I noticed my coolant level kept dropping, but blamed my radiator cap not sealing properly. I don't want to even contemplate what this means. Someone please tell me there is another possible explanation? Apart from completely tearing down the engine, is there any way to test where the problem might be?