Trying my best
Full Access Member
Ok, i seen "coolant overflow and not overheating" then i hear "white smoke on acceleration" and that screams "headgasket" and maybe whispers cavitation, but im going to try and be optomistic on this one. when coolant gets hot it expands into the overflow, when it cools, the vacuum it causes pulls the expanded coolant back into the radiator. There are two reasons i can think of that it wont do this: 1) you have no coolant in the overflow to draw back into the radiator, or 2) there is a leak, either in the radiator cap, the line from the overflow to rad. headgasket, or worst case scenario, a crack / hole in a cylinder head /block. When the engine attempts to burn coolant, its white-ish, smell the exaust after its been running a minute, would you say it smells sweet at all?
Summary: head gasket failure, cavitation or a crack would explain the white smoke (coolant in the combustion chamber) and the unexplained coolant loss. Also, the unexplained pressure in the cooling system (the overflowing) could also be from pressurized exaust gases entering the coolant system via failed gasket or a hole somewhere it shouldnt be. Given that it seems the affected area is related to the combustion chamber, im going to vote that you had a head gasket go **** up on ya. Most cavitation issues ive heard of are about midway down into the block. Course that doesnt mean anything, and it still could be a cracked head or something.
Thanks, I wonder about combustion gasses in the coolant. How do test for that?