loud clunk and white smoke started from under hood?

2008 PONTIAC G6
235,000 MILES • 3.5L • 2WD • AUTOMATIC
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RDEVADER
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Car was idling after running for approximately 15 minutes when heard a loud clunk and white smoke started from under hood. Turned the car off immediately. I was told it was probably the radiator. I had a Facebook mechanic put in a new radiator. Car still runs hot, still has obvious coolant leak. Also, after bad mechanic put in radiator car will not charge battery. (Did not have this issue before the new radiator was put in.)
Feb 17, 2025 at 5:06 AM
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STRAILER
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Yep, it is difficult to find a good mobile mechanic because the good ones work in a shop. It sounds like you have two problems, please start a new thread for the charging issue. For the clunk noise and the overheating can I ask if you heard the cooling fan running while this was happening? If not, I would replace the thermostat. Here is the location and how to change it out which should fix the problem. Check out the images (below). Please upload pictures or videos in your response of any problems so we can see what to help you with.
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Feb 18, 2025 at 10:26 AM
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