Coolant boiling after changing water pump?

2010 CHEVROLET IMPALA
200,000 MILES • 3.5L • AUTOMATIC
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CHRYSLER 01
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coolant is boiling after changing the water pump .. coolant is boiling when i try to bleed air out the system



... fan works t-stat is a few month old
Jun 6, 2026 at 4:02 PM
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CHRYSLER 01
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I have a spill-free funnel
Jun 6, 2026 at 4:04 PM
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CHRYSLER 01
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i install new coolant temp sensor
Jun 6, 2026 at 5:00 PM
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STRAILER
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Yep, that might be a bummer, let drain a small amount of coolant out of the system and do a head gasket test to see if there are leaks. You can have a blown head gasket without coolant in the engine oil fyi.

https://www.2carpros.com/articles/recognizing-the-symptoms-understanding-a-blown-head-gasket-in-your-vehicle/

and

https://www.youtube.com/watch?v=5zpNjYmmiYY

Please go over this guide and get back to me. Let me know how it goes.
Jun 6, 2026 at 11:25 PM
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CHRYSLER 01
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I don't have the equipment to do that
Jun 6, 2026 at 11:50 PM
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STRAILER
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You can rent it for free from the auto part store.
Jun 7, 2026 at 2:14 AM
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CHRYSLER 01
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I don't think it's that , cause It doe not overheat has soon has u start.

Jun 7, 2026 at 4:07 AM
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STRAILER
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It wont over heat as soon as you start it. A blown head gasket while take a while before it overheats. You may have a defective thermostat as well. Does the engine make a thumping noise when it is overheating, also is the cooling fan on?
Jun 8, 2026 at 3:06 PM
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