Re: is there anything like this for cars?
Could be air pocket, bad thermostat or pump (even if new), thermostat in upside down (easy to do), blockage in a hose, heater core or in the block, blown head gasket would dump antifreeze in your oil and vice a versa - dipstick would be milky looking. Try yanking the thermostat out and running the motor with the cap off the radiator, should see coolant moving. Did it ever actually overheat or just pop the excess out of your reservoir? It might have to boil down to its own height. If there is an air pocket, it should work it out on its own. The valves on the 2.9 are hydraulic not solid, only the 2.8 is solid and they stopped making that in 1985.<br />Mike