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Q: thermastat stuck removed now the car isnt regestering hot but can hear boiling from motor

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Thermastat removed no leaks not reg hot but can hear boiling from motor rad not smoking ac used to make. Knocking sound now that has stopped an not working at all

My car has 1700000 miles.

A: First off, you need a working thermostat in...

First off, you need a working thermostat in the car for it to function properly. If you removed the thermostat to fix an overheating problem, you will need to install a new one and begin the process of diagnosing the problem.

You state you hear boiling from motor. Hearing boiling or the rushing of water is usually due to the cooling system being low or there is an obstruction in the system.

The first thing that needs to happen is the installation of a new thermostat and to make sure the cooling system is full. To do this, once the thermostat is installed, fill the system, run the motor until the thermostat opens with the radiator cap off. You will know the thermostat is open when the hose attached to the thermostat housing gets hot. I recommend this tool for running a car with the radiator cap off.

It allows the coolant to expand as the car warms up. Once the thermostat opens, the level in this large funnel will drop and you will need to add more coolant quickly. Once the level stays constant and the thermostat is open, you can begin to diagnose what I assume is an overheating issue.

If you did install a thermostat and you hear what you describe as a boiling, you need to make sure the cooling system doesn't have any bubbles in it. You do this by following the procedure with the tool I recommended. This will allow any air in the system to eventually escape out the radiator neck. This can take awhile, so don't be alarmed if this bleeding takes as long as an hour.

This is just a place to begin. I am not sure exactly what is going on with your car from your description. I'd recommend getting your vehicle looked at by a qualified technician who can diagnose your overheating issue and other symptoms you've described. Once this is done, an accurate repair can be made to get your car running normally again.

Good luck.

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