I have a 54 Chevy 210 sedan. It has a 230 out of a 66 chenille with manual transmission. Wife was driving it on Sunday says she noticed a creamy substance on the bumper. She drove home about 2.5 miles parked it in the yard. When I opened the hood I noticed oil dipstick was not seated and there was oil on the hood. I notice the milk shake around the radiator cap. After the car cooled I opened the cap and it was all creamy and thick. I believe it to be a head gasket. I checked the oil levels and it was low. But no cream on the dipstick. Anyone have any idea other than a head gasket.