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Q: Thermostat isn't getting any hot water to open up.

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Symptoms: Over heating Cold air only out of heater Reserve tank overflowing

I've flushed my radiator and engine, however the heater pipes were clogged up.

As the car cools I can see the water pipe out of the engine implodes. When I open the radiator cap is sucks in air like it was gasping for air.

Overheating temp gauge, the water pipe out of the engine is hot however the one at the bottom that leaves the radiator and leads to the thermostat housing is cold and high pressured.

I suspect the hot water out of the engine should be passing through the radiator and cooling, however not so cool that the thermostat won't open to replenish the water in the engine block.

Any ideas of what could be causing this?

My car has 70000 miles.
My car has a manual transmission.

The hoses are collapsing due to the radiator cap and passage to the overflow is clogged. The cap needs to be replaced and the passages to overflow cleared. If the thermostat is not opening then replace it also. Make sure to flush out entire system and replace radiator and heater core if clogged and cannot be cleared.

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