You said your adding more coolant. Is there any leaks? Or is it boiling over?
When the engine is at operating temperature feel the radiator hoses and heater hoses for temperature differences. Is there any hoses colder than others?
If there are no leaks and you removed all the air in the cooling system (from the repairs) then the only thing left is a blown head gasket. Any air in the cooling system or loss of pressure (IE radiator cap) will lower the boiling point and cause overheating.
There is a test that uses a chemical reaction to determine combustion gases inside the cooling system and thus meaning a leak from the combustion chamber(s) into the cooling system (this is more rare but could include a cracked cylinder head or engine block).
The only name for this test I know is a "block chek" tester this test will tell you whether you have a major engine component failure or not.
Please answer my questions so I can narrow down the possibilities. I could be something simple as a radiator cap that is no longer holding pressure resulting in overheating.
Thursday, December 12th, 2013 AT 7:26 PM